1990 Toyota Celica Engine Oil Leak

HI I have a question regarding an oil leak on my Toyota Celica 1990 with 160000 mi. When I bought the car I drove it home and made around 6 miles. Once home I checked the engine and found no oil traces on the dipstick. I filled up the engine to the full mark, right a way I realized the engine was liking with drops every few seconds, 2 hours later there was a nice stain of oil on the newspaper I placed underneath. For the last 2 days I have been driving the vehicle with no problems, no noises, no noticeable engine lack of performance, it seems that it runs great, surprisingly I do not se big changes on the dipstick level. My question is let's assume that the car had been driven before me without oil for a while plus the 6 miles I put in, does that indicate that sooner or later the engine will break down when least expected or in the other hand will it survive many years it the car is service correctly. Thank you for listening.