Can someone help me?

Did you test drive it ?

Have the car towed to a mechanic or transmission shop. It could mean a rebuilt transmission to a simple solenoid fix. Nothing you can do in your driveway.

First & reverse are one thing; higher gears are another. If the transmission has problems shifting to second and higher gears, it's likely a shift solenoid problem that was caused by lack of servicing the transmission. You'll probably find fluid that's low, dirty, or even burned, and if you have a filter, it's clogged. This can cause a transmission with even new shift solenoids to malfunction. Replace the fluid and if necessary, flush the transmission..... If your twenty year old MB has this problem, it's likely that maintenance for the entire car was neglected, so have a mechanic do a complete job; it's costly, but cheaper than destroying the car.

Was it stuck in 1st gear before you bought it? I hope you got the car free.

Most of the transmissions are sealed so servicing them was deemed unnecessary by the manufacture, and so now you find out the results. Most likely you will need a new transmission.

No. I got it at a very good price. I drove it from the location I bought it to my residence. That's about 5 miles.

You got it for a good price for a reason. Sorry, to have a rebuilt automatic transmission installed in your car your looking at around $2 to 3K.