HGG Community Forums

To answer the original questions:
Futurity prospects are foals that are sired by a stallion that you do not own, and are the same era as that stallion. The stallion need 10 qualified foals to make the board. If he has more than 10 qualified foals, only the top 10 foals based on points from showing count. Foals are qualified from when they are born until they turn 6.
Eras are a whole different thing, and I can explain that if you want me to.
You make them by breeding to another player's stallion. You have a basic upgrade, so you can use straws to breed, make embryos, or you can do live cover.
Stallions are advertised in the era chatrooms and forums. Some players have their own forum thread to advertise their stallions, some don't, but there's a monthly futurity swap in the Games, Contests, and Giveaways forum where you breed 5 foals to the most recent stallion posted, lock them, post a link to those foals, then post your own stallion to be qualified.
This was this month's swap...
https://mesa.huntandjump.com/forum/index.php?p=/discussion/8764/futurity-swap-game-october-2024-special-for-this-month-big-raffle-prizes#Item_72
You don't absolutely need to lock them, but some players strongly request that you do because some players (apparently) just breed to send to auction or send back to the game. I have had it happen to my own stallions, which is why I like advertising through the swap game.

To correct some things mentioned above:
Mare's foals don't have to be owned by another player. There are no mare futurities. I have had mares make the board that I owned and only I bred to.
With a basic upgrade, you can make and sell embryos, but not eggs.
Era boards don't need locked foals, the foals can be from your own stallion.
Futurity boards don't NEED locked foals, it's just an extra level of security to ensure that it can't be sold back to the game. Locking does not increase training ability or show value.

You can make them and use them. You can't collect eggs.