Temperature gauge goes high and than causes engine light to turn on. Heat also does not work and smells hot.

Need to find out why it is squeaking there is no sounds when turning or difficulties when turning wheel it sounds like it's coming from power stearing pump or around it No pulleys are loose and belt is not wet or in bad condition need advice before pay for part and change it and turn out to not be problem.

Seems like the switch under the on/off button is broken. Can we fix this ourselves, or is it a dealer issue?

Last week on Friday I noticed my Check Engine light on as well as the VTM-4 light.
I check the manual. I redid the gas cap. After several drives and refilling the tank, they went off. I drove the entire weekend with no problem. Tuesday mornig this week they are both on again. I replaced the gas cap, no change. I had the oil changed, no change. I even diconnected the battery. The lights were off for about 30 minutes and are now back on. Thursday evening I noticed the "side airbag off" light is now staying on. The car has some other problems such as the doors no longer look/unlock by the electric buttons and must be done manually.
The car seems to be driving fine. We do not have money for repairs and must have this car running. Is this something I can fix light a sensor replaced or something?

Problem first evident this May... during first warm spell.

Last summer, I started having an issue with the climate control. When the weather started getting cooler, if I switched from A/C to heat, it wouldn't switch back to A/C with the climate control knob. After a few trips and a few more tries, it would switch over. After we switched it to heat for the winter, it obviously wasn't an issue. Now that the weather is heating up, we desperately need the A/C back on, but can't get it to switch back. Even with the unit completely off, heat seeps out. Any help would be appreciated.

averaging 8 miles per gallon

Is this estimate reasonable?
What can be damaged if not replaced?

This doesn't seem to affect the handing of the vehicle. However, when the light is on I can't shift into the lower gears. I successfully followed the owner's manual instruction to turn this light off. But then it comes back on in a short time of driving.

My pilot makes a knocking sound when idling. Could this be sticking lifters ?