看到输出下面的结果，就基本成功了，但是还差设置默认
By default, binaries installed by gem will be placed into:
/opt/homebrew/lib/ruby/gems/3.1.0/bin
You may want to add this to your PATH.
ruby is keg-only, which means it was not symlinked into /opt/homebrew,
because macOS already provides this software and installing another version in
parallel can cause all kinds of trouble.
If you need to have ruby first in your PATH, run:
echo 'export PATH="/opt/homebrew/opt/ruby/bin:$PATH"' >> ~/.zshrc
For compilers to find ruby you may need to set:
export LDFLAGS="-L/opt/homebrew/opt/ruby/lib"
export CPPFLAGS="-I/opt/homebrew/opt/ruby/include"
中间有提示
echo 'export PATH="/opt/homebrew/opt/ruby/bin:$PATH"' >> ~/.zshrc
终端中执行这段命令就好了。。
设置完还是不行，这是还差一步，这一步很多人没说，导致我也郁闷了一把，
一般是重启终端就好了
有时会遇到重启终端时——.zshrc报错not found……
这是你在/你的用户名/.zshrc 这个文件下，保存了错误的命令，用文本编辑打开这个文件，删除报错命令就行
没找到.zshrc文件，是你隐藏了文件，使用cmd + shift + . 快捷键显示隐藏文件
