Mario, You should be able to patch the tear with a good patch glue and a piece of vinyl. We recommend pool glue from Bond adhesives. You can smear it on the patch and it will even work under water. Just be sure to cut the patch larger than the tear. The next step is to make sure the filter is working. Hopefully there are no leaks in the lines. You will need to refill the water up to about halfway across the skimmer opening.
Then you can try to scoop out as many leaves as you can with a leaf rake.
Once the filter is operating you will need to shock the pool with at least 10 lbs of shock treatment or 10 gallons of liquid chlorine. You may need to repeat this more than once. Once the pool starts to clear up, you will be able to see to vacuum. Hopefully this will do it and you won't need a new liner. But if the pool is more than 15-20 years old, it may not be a bad idea to invest in a new liner anyway.
Good luck.