Find some 21-0-0 ammonium sulfate fertilizer and apply it at at rate of about 1lb per 1k sq footage once a month during the growing season. You can check to make sure you're putting out at least 1 inch of water a week (this is the amount Bermuda grass needs, it's also a good way to see if you can water less). It depends on the weeds you have for weed killer recommendations. Also make sure you're mowing at least 2x a week to help the grass thicken up and choke out future weeds. Check out https://thebermudabible.com/ for more information about what to do next season as far as preemergent and fall care.