Mobs models exist in world but i can't do anything with them.

I made a flat redstone ready world and teleported to the edge of the world using commands, then, I teleported again to a random location using commands and saw mob models(Like:Creeper,Spider,etc) then I changed my game mode to survival and they didn't do anything! I did /say @e and it didn't say Creeper or Spider or anything! it just said the items' names I just throw.
Note #1: The models have colliders.
Note #2:The mobs can't get on fire.

EDIT:Even mobs I spawn from mob eggs do the same.