Each headlight has a separate motor that raises them and lowers them. Sounds like they need replacing. They're located under the headlight housing unit and hard to get to, so I'd recommend taking it to a mechanic.
Most likely a fuse.
Possible ground issue at the taillights.
A bad ground wire will cause dim headlights, or will cause lights not to work.
probably the fuse is blown.
On a 1999 GEO Tracker, a bad fuse can cause the headlights and dash lights to blink. A bad voltage regulator or alternator can also cause lights to blink and flicker.
Theres a switch 2 buttons to the left of the defroster switch. That switch is to raise and lower you head lights without turning them on so you can change the headlights. The switch could have a short in it causing it to act like that.
If the headlights are on and brake lights work but not the tail lights, it is possible there is a short in the electrical wires. Another cause for this could be that the tail light bulbs are burned out. Most vehicles have more than one bulb inside the tail lights to control different lights at the same time.
A mis-wiring or short circuit somewhere between the controls, fusebox and lights.
have you tried turning the ouside dial on headlight switch that dims the gages bright or dull had a similar problem with 98 corvette no dash lights or hvac or running lights turned out to be multi function switch (headlights turnsignals)
Blinking lights on dash and exterior lights may indicate a bad ground wire or a faulty headlight switch. Both would cause those problems.
Fog lights. Headlights and hi beams can make foggy conditions at night much worse because their light tend to illuminate the fog directly in front of your vehicle. Because Fog lights are much lower on the front of your vehicle don't cause this problem and you can see a bit futher. the fog lights
sometimes the head lights and tail lights may be fused separately,check your fuses.you could have a bad ground.thats just two places to start.