4 month old learning. Please help mamas!!!

My little boy is 4 months old. He can lift his head up real well and he can even roll from his tummy to his back. I think he has been teething. There's no use in giving him a pacifier because he never uses it. He just uses his fist 😂 I am some small teethers and I try to them to him but he doesn't quite have the grip to hold it for long periods of time but his strength in his hand is really sting though. I this normal??? I need help. I don't know what kind of toys to get him or learning toys. Can someone please give me advice on what to get !!!!!!