[Water Warrior 2]

Wow, looks like a brand new bike in the pic. Congrats and welcome to the forum. Heck of a find. The good news is the bike is yours to ride. The bad news is you have to spend some money and time on it. No matter how much tread is on the tires they should be replaced due to old age. Rubber gets hard and slippery with age so it won't grip like it should. As a rule of thumb tires that are 5 years old should be tossed for safety and reliability.
You should also change the brake fluid for the front brake too. Just for fun and knowledge you should go over the entire bike to check for loose nuts and bolts. It is a great way to get to know the machine and find out where stuff should be and what it looks like while it still looks new. Lube everything that moves too. The sense of satisfaction is good for you and the bike will appreciate the TLC.