1991 buick regal 3800

Probably needs servicing. Could be a setup issue, could be worn plugs could be dodgy fuel etc etc etc.

on the charging problem take it to almost any parts store and they will check out your charging system for free

Higher cold cranking amp rating on the battery. 850 or higher. Those old Buick motors get heavy in the cold

Volt light on indicate the altenator is not charging the battery the temp light means it's over heating and difficult steering means the power steering isn't working properly.
Common to all of these would be your serpentine belt which drives all of these items. have it replaced

replace the ignition module,under the coil pack.

Then it has to be fuel, compression, or air. Check for fuel pressure first, if it has fuel pressure check for compression, must have a minimum of 100 pounds to run. Last check for air supply being restricted(very very very rare). if it has all of these and sprk it has to run as long as its timed right which is impossible to get out of time on a fuel injected engine like this unless someone mixed the plug wires up on the coil pack at which point it will be back firing out the intake and exhaust.

egr valve is not opening up when the engine reaches it normal operating temperture

First things to check would be fuse(s) at dash & under hood, as well as rad fan relay & possibly coolant temperature sensor.

change the starter relay located in the fuse box in the engine compartment near the battery.

I have found the most common part failure issue with the ignition system is the crank sensor, also called by some the TDC sensor.