For a UVB, that light is fine.
bbyoda is correct; you will also need a basking light (old-fashioned incandescent, flood, or halogen flood). DO NOT use an LED bulb—they do not produce enough heat—and DO NOT use a 'spot light' of any kind. Spots produce hot spots, which can burn; floods or household bulbs produce
gradients, so your chameleon can choose the warmth it desires.
You will also need a plant light. LEDs
are the best for
plant lights. This one is excellent for a 24 x 24 x 48 enclosure—it is self-contained (no separate bulbs & fixtures) and warrantied for 5 years—but there are others as well.
https://www.amazon.com/SANSI-Daylight-Lights-Indoor-Plants/dp/B07TKKG8Q3
coupons
Chameleons (and other basking reptiles) will try to bask under the
brightest (rather than warmest) light they can see, which is often the plant light. One solution is to mount the basking light at an angle, aiming at a spot (basking site) directly under the plant light. A secondary effect of this is producing the desired basking temperature gradient mentioned above.