Hi and welcome! First would you fill in your profile to show us your location? This will help us to advise you. Just a zone doesn't help much because it only tells us how cold you get in your average winter.
It's fun to grow these as tropical plants, but don't let your expectations get too high. Unless you plan to move to South Florida? If you are growing mango into a tree outside its zone, without a large greenhouse and a lot of supplemental lighting and heat over the winter you have very little hope of ever seeing fruit or even flowers on your mango tree. In addition, growing a mango from a seed, the plant will take at least 5 years to get big enough to flower even if you can give it enough sun and warmth. Then you will have trouble getting it pollinated, as the pollinator is a specific type of fly.
Sorry to be discouraging but . . these are large tropical trees with high demands. My mango tree flowers any time between January and the end of March, and then it takes all the way until June for the fruit to ripen.
