So the spot is getting larger over time? If so, probably not a burn but could be either a bacterial or fungal infection. Can't tell which from the pics. Antibiotic ointment could treat a bacterial infection but may not have any effect on a fungus or a virus. A vet may help diagnose what it actually is and prescribe the correct med to treat it.
If it isn't getting larger it could be a thermal burn. You can help heal it with an antibiotic ointment like Polysporin or Silvadene (ask the vet for a sample). Then, double check your basking light temps at the perch where the cham would sit and move the light farther away.
I do see another possibility. It looks like your heat lamp is hitting one of the black PVC rods that make up the framework of enclosure. Those things can get super hot. You might check the temperature of that rod. If your chameleon can get close enough to brush it, that might have caused a burn.
So I took Rango to the vet today she said it is bacterial infection he was given a shot of antibiotics and I have some antibiotics I have to give him once a day and whipes I'm supposed to put on the infected areas so I guess theres nothing else to do now bit wait...wish him luck...he hasn't lost his appetite so i think he will do fine
That's great that you were able to get him to the vet to find out exactly what is it and get proper treatment. I think he will do well now that he is receiving medication and your daily care