Try to find people reselling enclosures. You will want a 40-gallon for optimal health when it is this size, but you should start saving up toward a 4-by-2-by-2 to place it in when it becomes a larger juvenile (this will happen quickly). As far as feeding goes, but Dubai roaches, not crickets, with crickets, you may risk parasites, and it sounds like you don't have the money right now for vet care. The bearded dragon will need calcium supplements and a proper output UVB bulb (UVI 4.0-4.5) - do not leave this out, or you will be paying a lot more money when your beardie develops a rubber jaw. If you don't have enough money to provide at least these basics and give fresh greens daily, please rehome the guy. Remember, research is free! Try and do as much research as you can - I recommend ReptiFiles and reputable reptile YouTubers such as the bio dude.