rails s

Traceback (most recent call last):
        27: from bin/rails:3:in `<main>'
        26: from bin/rails:3:in `load'
        25: from /Users/yamabasic/bin/spring:15:in `<top (required)>'
        24: from /Users/yama/.rbenv/versions/2.6.4/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
        23: from /Users/yama/.rbenv/versions/2.6.4/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
        22: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `<top (required)>'
        21: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `load'
        20: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/bin/spring:49:in `<top (required)>'
        19: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client.rb:30:in `run'
        18: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/command.rb:7:in `call'
        17: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `call'
        16: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `load'
        15: from /Users/yamabasic/bin/rails:8:in `<top (required)>'
        14: from /Users/yamabasic/bin/rails:8:in `require_relative'
        13: from /Users/yamabasic/config/boot.rb:4:in `<top (required)>'
        12: from /Users/yamabasic/config/boot.rb:4:in `require'
        11: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/setup.rb:2:in `<top (required)>'
        10: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/setup.rb:2:in `require_relative'
         9: from /Users/yambasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap.rb:5:in `<top (required)>'
         8: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap.rb:5:in `require_relative'
         7: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache.rb:61:in `<top (required)>'
         6: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache.rb:61:in `require_relative'
         5: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `<top (required)>'
         4: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/explicit_require.rb:41:in `with_gems'
         3: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `block in <top (required)>'
         2: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `require'
         1: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack.rb:8:in `<top (required)>'
/Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack.rb:8:in `require': dlopen(/Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle, 9): no suitable image found.  Did find: (LoadError)
        /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle: mach-o, but wrong architecture
        /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle: mach-o, but wrong architecture - /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle
        28: from bin/rails:3:in `<main>'
        27: from bin/rails:3:in `load'
        26: from /Users/yamabasic/bin/spring:15:in `<top (required)>'
        25: from /Users/yamag/.rbenv/versions/2.6.4/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
        24: from /Users/yamag/.rbenv/versions/2.6.4/lib/ruby/2.6.0/rubygems/core_ext/kernel_require.rb:54:in `require'
        23: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `<top (required)>'
        22: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/binstub.rb:11:in `load'
        21: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/bin/spring:49:in `<top (required)>'
        20: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client.rb:30:in `run'
        19: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/command.rb:7:in `call'
        18: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `call'
        17: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/spring-2.1.1/lib/spring/client/rails.rb:28:in `load'
        16: from /Users/yamagibasic/bin/rails:8:in `<top (required)>'
        15: from /Users/yamabasic/bin/rails:8:in `require_relative'
        14: from /Users/yamabasic/config/boot.rb:4:in `<top (required)>'
        13: from /Users/yamabasic/config/boot.rb:4:in `require'
        12: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/setup.rb:2:in `<top (required)>'
        11: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/setup.rb:2:in `require_relative'
        10: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap.rb:5:in `<top (required)>'
         9: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap.rb:5:in `require_relative'
         8: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache.rb:61:in `<top (required)>'
         7: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache.rb:61:in `require_relative'
         6: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `<top (required)>'
         5: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/explicit_require.rb:40:in `with_gems'
         4: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/explicit_require.rb:44:in `rescue in with_gems'
         3: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `block in <top (required)>'
         2: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/bootsnap-1.7.5/lib/bootsnap/load_path_cache/store.rb:4:in `require'
         1: from /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack.rb:8:in `<top (required)>'
/Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack.rb:8:in `require': dlopen(/Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle, 9): no suitable image found.  Did find: (LoadError)
        /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle: mach-o, but wrong architecture
        /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle: mach-o, but wrong architecture - /Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle

 dlopen(/Users/yamabasic/vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle, 9): no suitable image found.  Did find: (LoadError)

ここに記載されているように

vendor/bundle/ruby/2.6.0/gems/msgpack-1.4.2/lib/msgpack/msgpack.bundle

ここの部分を消去して
もう一度msgpackを入れ直す

bundle exec gem install msgpack

そしてbundle installをする
するとrailsコマンド使用できるようになる

もし解決しなかったらエラー文が出てくるので今度は同じ感じで消していきgemを入れてbundle install　を実行を繰り返す