After xcode13 is upgraded, if a new project is built, pod install will report an error, as shown in the figure:

Reason: This is because the local version of Xcode does not match the version of cocoapods. You need to update cocoapods
solution:

Refer to the solution provided on the Internet and input the command at the terminal  $ gem install cocoapods --pre  

Error will be reported:     You don’t have write permissions for the /Library/Ruby/Gems/2.6.0 directory.

  Solution: input in the terminal     sudo gem install -n /usr/local/bin cocoapods –pre

It can be used normally in pod install