Welcome to the forum! I'm glad to see you're getting everything set up ahead of time. It will make a big difference for your new buddy. I'll be glad to help get everything configured so it's just right.
What equipment do you have in place so far? What is the size/dimensions of your enclosure?
To answer your question you can change the temperatures by using different wattage bulbs, raising/lowering the basking light (adjustable lamp stands are helpful), and some bulbs can be dimmed to fine tune the output (halogen flood lights in particular). I have mine hooked to a dimming thermostat which I find very helpful but it's a luxury item to an extent. Worth it if you have the budget but I wouldn't put it at the top of the list if resources are limited (UVB lighting is top).
You can upload photos of what you have here
https://www.beardeddragon.org/useruploads/ and post them to your thread using the XIMG button if you wish.