So good that you are going to look after the poor guy. If you hadn't found him he would have died a fairly slow death.
His eye is swollen and he shows signs of MBD in his right arm so a vet visit would be good.
The regular household incandescent light bulb in a dome hood is all you need for basking. The most often recommended UVB light is the long linear ReptiSun 5.0 tube light. Basking temperature in the mid to high 80's ..make sure the bulb isn't so close to the top of the cage that he can end up burned if he hangs under it....hold your hand at the closest post he can get to it and if you don't have to move your hand away it should be ok.
You can make a dripper from a deli cup that has a very small hole punched in the bottom of it so it drips at the rate of one or two drops per second and use a plant mister to mist the cage and of course you will need a plant to mist/drip on so he can drink. Make sure that the plant is non toxic and well washed ...both sides of the leaves. Pothos is one of the best plants IMHO.
Insects should be well fed and gutloaded and dusted with the appropriate supplements. Crickets, silkworms, hornworms, roaches, locusts all make good food for them superworms and waxworms can be used as treats. Crickets, roaches, superworms, locusts can be fed/gutloaded with a wide range of greens such as dandelions, kale, collards, endive, escarole, mustard greens, etc and veggies such as carrots, sweet potato, sweet red pepper, squash, zucchini, etc and a very little bit of fruit such as melon, apples, pears, berries can be used.
For supplements many people use the Repashy LoD but a lot of people also use these 3 different supplements...a phos free calcium powder at almost every feeding dusted lightly on the insects just before feeding them to the chameleon, a phos free calcium/D3 powder dusted lightly twice a month and a vitamin powder that contains a beta carotene prOformed source of vitamin A dusted lightly twice a month. The reasoning ...Most insects have a poor ratio of calcium to phos so dusting with the calcium helps make up for it. D3 from supplements builds up in the system and can lead to health issues so we only do it twice a month and leave the chameleon to produce the rest of the D3 from its exposure to the UVB. D3 produced from exposure to the UVB won't build up as long as the chameleon can move in and out of it at will. PrOformed vitamin A won't build up in the system like prEformed (palmitate, retinol, retinyl) sources will...but there is controversy as to whether all/any chameleons can convert the prO to the prE so you may have to give it a bit of prEformed once in a while.
Hope this helps! Good luck with the poor chameleon!
Definitely would like to see a photo of its butt with the white stuff on it.
