I hate this question, but it keeps coming up.
Converting usually requires a kit that’s installed in a very precise fashion and, after installation, the equipment is thoroughly tested before it’s considered SAFE. The kit has parts to change over parts in the the main burner, the pilot and the combination valve.
If the conversion is not done correctly, a potentially explosive situation exists. As a technician, I work with gas everyday. When LP enters the picture, my radar goes up. LP demands that extra attention.
If you must come on here and ask that question, then I have to assume that you don’t have the resources, the resourcefulness…or the proper knowledge to perform the task.
A conversion from natural to LP gas IS NOT a DIY project. Sorry. Can’t help you.