Can't run Jekyll on Monterey

Hi all,
Since I had problems after updating to Mac OS 12.0.1 I have now done a clean install of the OS and started from fresh. I haven’t made any progress though!

I have followed the instructions on jekyllrb.com to a T and installed ruby and Jekyll.

When I try to run the local server and run a website I created some time ago and which works perfectly from my another computer I get this:

Could not find addressable-2.7.0 in any of the sources
Run `bundle install` to install missing gems.

If I run ‘bundle install’ it does not solve the problem, I get the same error message over and over.
Do I have to be in a specific working directory to run this command?

If I try to create a blog from scratch and follow the steps:

Jekyll new test
cd test
bundle exec Jekyll serve

I get this:

“”
bundler: failed to load command: jekyll (/usr/local/lib/ruby/gems/3.0.0/bin/jekyll)

/Users/stephane/.local/share/gem/ruby/3.0.0/gems/jekyll-4.2.1/lib/jekyll/commands/serve/servlet.rb:3:in `require’: cannot load such file – webrick (LoadError)

“”

Does that mean I have a PATH problem? Here’s my PATH variable content in case that helps:

/Users/stephane/.gem/ruby/3.0.0/bin
/usr/local/opt/ruby/bin
/usr/local/lib/ruby/gems/3.0.0/bin
/usr/local/bin
/usr/bin
/bin
/usr/sbin
/sbin

Thank you for any help you can provide.
Stephane