So someone else at my table, and I both picked the spell enlarge/reduce. We typically go off of descriptions in we get off of a official dnd website. The spell says it makes you 8x larger, or smaller, but when enlarging you stop growing if you're in a space with a ceiling and you reach the ceiling.

1st & 2nd question if we are in say a cave and there's an enemy the party can't beat. If my other party member and I both cast enlarge on the enemy, and they fail their saving throw. Could we technically make them so big they'd be stuck and unable to move allowing us to escape? Or does it not work like that?

3rd and 4th question if we were outside and we're facing the final boss, and it's a dragon could we turn our barbarian into something as big as a titan from attack on titan to even the odds? Would it matter cause it doesn't make the barbarian stronger just bigger?