I am a senior in highschool. I use to be social but after my depression I seem to have become antisocial/introverted.

I want to talk more with my friends and I want to make more friends and hangout more but I never have anything to say. I can never think of stuff on the spot and end up not saying anything for more than a whole lunch. I want to initiate conversation but can never think of what to say. I don’t go out much with my friends because they are friends with other ppl and often go to their houses on the weekend but I don’t know their other friends so I don’t get invited

Im looking for tips or suggestions on how to break out of this honestly.