but the upper knob is probably a feed reverse . . . at least it's in about the right place for one on a belt-drive unit. It might also be associated with a back-gear, but belt-drives often have a sliding-pin arrangement for that function inside the headstock somewhere.
in any case, there will be a placard near it with an ideogram that will be more-or-less self explanatory. . . though you might have to use a little process-of-elimination thinking.
the lower-right lever is probably the selector for feeds or threads, and again will have an ideogram indicating which position does what.
Tip: if you know the model number, call up enco and see if you can get a .pdf of the owner's manual to study up on before you go see it.