How to fix my car door locks?

I have a '93 ford truck I bought it and my keys don't unlock the door
I have two keys one for the back window and one that works for the ignition
the back window key doesn't even fit
but the ignition key I thought was the key for the door as well will fit in the key hole but won't turn (driver or passanger side)
I can lock and unlock the doors from the inside
but the keys don't work so I can't lock it when I leave it
and I don't know even how to start fixing the issue
should I go to an auto shop? Lock smith? Can I fix this myself?

They do sell new door lock set for around $40 from a professional part store and online. Check with a locksmith if they can make the key for yours for less. Meanwhile have the locksmith make another ignition key if that is your only one. Or forget about it and be sure to have two working remotes.