Regarding fins, the first choice you have to make is full foot vs open heel. Well over 90% of the divers I know and see chose open heel fins.
If you go down that road, get your booties first and when trying them on they should feel like any well fitting athletic shoe. While it may seem unlikely, you might have to walk some distance in them. I know that I have over the years. For my tastes, the harder the sole the better.
When you have good fitting booties, start looking at fins. Your foot, the booties and fins work as one unit and should be well matched. For me, some Scubapro fins are a tight fit top to bottom and Atomic fin pockets tend to be too wide allowing the fin to shift from side to side. We have different feet, will wear different booties and probably dive with different fins. It's all about what fits you. I wouldn't be afraid of shopping at different dive shops in your area looking for the "perfect fit".
Two things I really wish I had bought for my open water course are a neoprene strap for your mask and if you still have an extra $40-50 bucks, spring straps for the fins. Lot of time spent in OWC putting on and taking off both your mask and fins.