I just changed out our kitchen sink faucet. Removal of old and installation of new went well... the problem is the water hook-up. The new faucet fittings are 3/8" compression fittings. The water lines from the new faucet to the water shut off valve are a PVC type. The old faucet had copper tubing out of the sink faucet then a connection of plastic/PVS that connected ot the shut off. The fittings to connect the old faucet to the water shut off are larger than the 3/8" that I am dealing with on the new faucet, so consequently they don't fit. The instruction manual diagram indicates that you insert the cold/hot water line hose from the new facuet into their respective shutoff valve and use the nut that is on the new hoses to secure. Obviously, because of size difference this is not possible. My questions:

Is there some sort of adapter that will make the new hoses fit to the water shut off or should I change out the shut off valves to match the new hoses?

If I have to change out the shut-off valve, how do you do this? The valves appear to be soldered (spl?)/permanently connected o the copper pipe that comes out of the wall. I am relatively handy, but have limited (very) experience with plumbing. Any insight into this situation would be greatly apreciated... my wife wants her sink back!