I own a 3 flat and after shutting down the water from the shut off valve, upon turning it back on the water pressure has not been the same. There is a lot of noise in the pipes when
Turning on the water. And the Water tank girggles some times, when it never did this before. It sounds like there could be air in the lines. What can I do to solve this problem?

If you have a gate valve, the gate valve may have failed and not opened as it should.

Check for sediment caught in the screen of the faucet.