You should not be seeing foamy bubbles like that at the surface of the water. I would stay away from meds for now. Water changes and a proper amount of aquarium salt will help cure the fish and heal the damage. You'd be amazed at how well simple aquarium salt can help heal all sorts of bacterial and fungal infections. Once they are back to health a regular water change routine will keep your water quality up. Also when you clean your filters only clean the mechanical filtration portions. Leave the bio media alone to preserve your beneficial bacteria so your tank doesn't have to cycle all over again. There are plenty of resources online to teach you all the basics. KG Tropicals on YouTube makes tons of videos with a focus on new fish keepers. Aquarium co-op is another good source of information. Once you start researching you'll find there are many others as well.