1994 Ford Ranger headlights won’t work...

My 1994 Ranger had the headlights
go out. They only work when I pull
the arm to flash the hi-beams.  When
I let go of the arm, my headlights
don’t work. My turn signals, interior
and running lights still work. When I
had my hi-beams on the day before, I
did smell something burning. How do
I know if it’s my multipurpose switch,
or my main headlight switch?  And, if
I do replace them, how do I know if
the wires running into them are still
good?  Maybe that’s why I smelled
something burning. Lastly, is this
something that a novice can easily
fix?  I have the tools, but no
experience. Thanks in advance