Tips on flying with a toddler?

Has anyone ever flown with a toddler ? I’m looking into flying alone with my two year old . I’ll have to take his car seat with me . Do I have to have gate check it ? Or is it easier to check it with my bag before security ? I really don’t wanna lug it thru the whole airport if I don’t have to . And Ik it’s not airplane approved so he can’t sit in it anyway .