~ばいい and ~ばよかった are a great way to say "should" in Japanese. Chie and Ty explore this N3 grammar point and Ty talks a bit about his experience with the N1 using this language as well.
Want to learn Japanese? NativSharkに登録すればいいよ。(You should sign up for NativShark): https://www.nativshark.com/lbjp
Show notes here: https://www.nativshark.com/tools/using-nativshark/lbjp-ba-ii