Debug a flutter project (flutter 2.10.5)

I have a flutter project whose version is 2.10.5 (Mac). It's throwing a bunch of "null safety" related errors when I try to run it. It was originally developed in version 1.4 and upgraded to null safety but I think the upgrade job wasn't done very well.

I also need you to see if it's upgradable to a more recent version of flutter and replace any outdated libraries.