What are you looking for protection or looks. A wax will not last as long as a sealant, but a wax will add depth to your paint. Sealants tend to look better on light colored cars as wax's look amazing on dark cars. I use both it just depends on the time of year and the color of the car. Other factors I consider are:
Where is the car parked most of the time?
How often is it washed?
How often is is waxed/ sealed?
A more important thing to consider is your polish, a great polish job can make or break how a cars paint looks, no matter what wax or sealant you use. I would go for a PO106FA polish, or a optimum polish, then chose a wax or sealant that fits your needs. I personally like Optimum, 1z Glanz Wax, and Z2, Klasse AIO is a great sealants. As for Wax's Megs M16 is my fisrt wax I go to, I have others but that is my go to wax. Just remember POLISH is the base to a kick *** shine.
Oh and :welcome there is a lot of info to take in but just go one step at a time.