All of the recruits are per-determined characters. The only one you get to make yourself is your avatar at the start. And the amount of characters you get is very limited, so they're all very precious.
If you'll like it if you like XCOM? Well, I like both, they're pretty different within the genre, though. Fire Emblem is not a sandbox SRPG, it has a linear story that you follow. Although to can fight randomly spawning undead on the world map for extra EXP between chapters. The gameplay might feel a bit similar, you have your Player Phase where all your units act and the Enemy Phase where all the enemies act. Since it's fantasy, you're mainly fighting with melee weapons or weapons that has a two tile range, meaning that positioning and blocking access to your more fragile characters becomes more important.
This is the first Fire Emblem where Permadeath is optional, though. In Casual/Newcomer mode you get defeated units back at the end of a mission. In Classic Mode... you don't. Ever. Meaning you lose that branch of the story and maybe characers that depended on that unit to be recruited. Like if Sumia dies, you don't get Cynthia either.
There is a demo, if you have a 3DS, maybe give that a try?