Welcome to TFP!!!
How old is your pool? Can we get some pictures?
Depending on your setup, age, and what you want there are ways to replace the metal conduit with nonmetalic conduit. But we would need to see and understand what you have now to help you.
Unless you are very very handy and have advanced homeowner electrical skills this isn't a DIY project. Pool electrical is , well, different. So a couple of suggestions:
Post some pictures here to show us the overall layout of your pool and where the light junction box is (if you know).
Second, I'd go get a couple of electricians with pool experience, preferably subs for local pool builders to come over evaluate your situation and give you a price. They can tell you different ways to do it and their price might be very reasonable (or crazy nuts high). But its a free expert evaluation.
If you get bids we are great at commenting on them.
