A bad title but there are so many issues!

I have had this car for 12 years. Shes got 200K on her roughly. I have replaced almost everything but the tranny and motor.

I have been chasing an oxygen sensor for as long as I have had the car. Replaced both the one under the hood and the other that runs to CC. No changes, still get the code. IS THERE ANOTHER?

My ABS light comes on when I turn, I just recently cleaned the connections and applied some grease. Problem is I am leaking major oil and she is parked now...so cant tell if the cleaning helped or not.

The oil leak we cannot find. Loaned the car to my kid (never again) and it came back with a ton of oil all over the pass. side of the engine. Hubby originally though it was a part that he damaged when replacing the starter but that wasnt it.

I had her up on jacks and compressed my rear shocks-is there any way to bring them back?

Thanks for any advice!