Before anything else: God loves you and likes giving you good things. Wanting things isn't wrong, and He doesn't get upset about your desires.
Think about that toy you wanted most in your whole life. The one you asked for over and over, that stayed on your mind for weeks, and that you thought was going to be the most amazing thing in the world.
Do you remember the day you got it? It was wonderful, right? It gave you that huge happiness, and you played with it nonstop.
Now answer honestly: where is that toy today? A lot of the time it's at the bottom of the box, under other things. And the funniest part is that, not long after, you already wanted something else.
That doesn't mean you're ungrateful, okay? It happens to everyone, even grown-ups. They do the same thing with cars, phones, and houses.
It's just that there are nice things that bring joy for a little while, and there are things that bring joy that never runs out. Playing with someone who loves you never gets old. Helping someone never gets old. Talking with God never gets old.
Jesus explained this in a beautiful way. He said that whoever drinks regular water gets thirsty again, but whoever drinks the water He gives gets a spring inside that never dries up.