For my baby panthers I try to keep their basking spot around 85-87F. The little guys are more succeptible to overheating.
Light bulb brand actually isn't terribly important. You don't need to buy an expensive reptile basking bulb. A regular household bulb will do the trick for now and a flood light type bulb will work when he is older and needs a little more heat in a larger cage. I can't recommend a wattage. Everyone's cage is different and it really depends on the placement and distance of the light in your cage. I would start with a 75 watt light and work from there. Take a lot of temperature readings, raise and lower the light as needed, or move to a higher or lower watt bulb.
As for distance, I keep my light at least 6 inches away from the highest point my chameleon's head can get to. You can use the clamp on the light fixture for this or use wood blocks underneath the fixture to raise it up. Again, this is mostly trial and error. Invest in a good temperature gun or thermometer with a probe and you'll save yourself a lot of worrying