HI Alan, here's a recipe to unclog it with vinegar and baking soda it does work I've used it in the past: https://crunchybetty.com/clean-your-drains-baking-soda-vinegar/
I would also suggest going under the sink and unscrewing the drain trap, that would give you access to the pipes to clean them out by hand too.
Advice above is perfect. I would additionally suggest to have a bucket or large pail to catch water & "yuck" if you check the trap.
Faucet?? not drain try removing the faucet screen it should unscrew from faucet tip then place it in cup with white vinegar or CLR to clean & remove mineral deposits.#1 https://www.youtube.com/watch?v=lNP-NYWsCyA #2 but soak in vinegar or CLR https://www.youtube.com/watch?v=e_DaEA5UtqY if that doesn't help it maybe clogged in valve/cartridge inside faucet https://www.youtube.com/watch?v=UZg6k8DdL0c