I HAVE AN AUDI A6 1996 MODEL I CANOT SELECT GEARS. ITS STARTS IN PARK AS PER NORMAL BUT JUST DOESN'T SELECT GEARS. WHAT IS THE CAUSE OF THIS?

It is not recommended to drive an Audi A4 B7 with a tiptronic gearbox in park mode. The park mode is intended to be used when the vehicle is stationary and the engine is turned off. When the vehicle is in park, the transmission is mechanically locked and the wheels are prevented from turning. If you attempt to drive the vehicle while it is in park mode, it may cause damage to the transmission and other drivetrain components. It is important to ensure that the gear selector is in the appropriate gear for the vehicle's speed and driving conditions before attempting to drive. If you are experiencing problems with the gearbox or are having difficulty shifting gears, it is recommended that you consult a professional mechanic for assistance.

Does this car have electronic parking brakes??

Check the gear box oil level sounds low to me i had a similar problem with a auto box car before and as for your steering it could be a worn steering rack if the oil level is good

You will have to tow the car out to a auto transmission specialist as the gears have seized in the gear box. You will cause more damage if you over ride the engine controls. The torque converter must be stuck.

Are there any check lights up on dash?If so have the car checked for fault codes by a garage or dealer able to read these and erase also.This could be caused by numerous issues,but I will cover some simple checks first.
1.a blocked fuel filter will cause the vehicle to loose power when under load;in gear.
2.a severely blocked air filter will do the same.
3.if transmission is faulty,usually the revs will climb readily but it will not dive well under load as it is slipping.
4.a blocked exhaust system,check by revving engine while someone checks at the tailpipe for exhaust blowing.If it has a flat muffled sound and very little output it may be blocked.
5.badly worn spark plugs,although they would usually cause a miss also.
6.contaminated fuel or fuel system,usually misses also.try a quality in tank fuel cleaner.
7.low fluid level in transmission.check the level as per manufacturer specs or in park,engine running.
8.air flow system,usually causes a check light on dash.
9.brakes dragging
I hope this gives you some areas to check,or get back with more findings or detailed description.

Since it is electronically programmed, it is best to
call your nearest Audi dealer service center to have it checked. Normally, replacement parts for
this kind of defect, is sold by them.

check your inhibitors switch or the shifting cable.

Release bearing problem.Change the clutch Assembly

check the linkage on the side of transmisson to see if it lose

After a jump start because of no electrical power, the car will run rough for several days (expected) while it adjusts to your driving habits. I'm not sure about the gears, but I'd try to drive with it like that for a few days and see if it returns to normal.