I'm not sure that the new number 1 would be a good jumping on point
Gene Luen Yang has given the Shang's whole backstory a soft reboot.
Added a bunch of new supporting cast members, new villains, extended family members and new locations and organizations
I'd say start with number 1 of the 2021 miniseries and catch up with the current volume just to get all of the backstory
I enjoy the book, but this is coming from someone who isn't too familiar with Shang-Chi from before the current run