They dribble every restart straight into three players

I’d start adding “look first” now, but I would not stop them dribbling the restart. At the moment they have learned one exciting thing: I can put the ball down and go. The next bit is recognising whether there is actually somewhere to go. Try giving them a couple of seconds before the restart and ask, “what can you see?” Sometimes the answer should still be drive straight in. Sometimes they will notice a teammate or a space to the side. In training you can exaggerate it by having the defenders start in different places so the picture changes each time. And yes, losing the ball is part of the learning. You do not need to rescue every bad restart. Just help them connect what they saw — or did not see — with what happened next.