Pop! OS: https://pop.system76.com/ is the Linux distro I recommend for basically everybody.

It's based on Ubuntu, which is based on Debian, so it has most of the community knowledge around support. It's the "happy path". Pop! OS is nice because it removes the bad part of Ubuntu, called "snaps", but keeps the rest.

The only thing I'm not certain about is using the external display. That's something you will probably need to figure out from googling ;(

As a side note: Befriending the command line is daunting, but pays dividends. A lot of the help online will recommend the command line. You can't avoid it entirely, and it's a superpower.