Jack up and prop axle so a front wheel is off the ground. Check for play by trying to wobble the wheel. It might be wheel bearings in which case you will hear them rumble.
Check all the steering linkages for play with a bar
Swivel is the chrome ball the wheel turns left and right on. The pin is under the plate with 4 bolts on the top of the ball. The amount of pre-load is adjusted but adding or removing shims under the plate. Too many shims and the whole wheel assembly wobbles, too few and the steering will be stiff and won't self-centre.
Considering you want front wheels to steer and not fall off you really need to know what you're doing so depending on your ability either ....
1-take it to a mechanic
2-get someone who knows how to show you
3-do a lot of research first