I have never changed a faucet before. Do I need to call a plumber? ( We called one who hasn't responded) It seems that today parts are easily replaced , unlike when I was a child when you had to use copper fittings with torches and pipe dope ,etc.

I looked at the faucet and saw two screws . I tugged slightly on the knob but it seem like it was a sealed unit and didn't budge. Please advise me what I have in store before I get myself in over my head.

Feeling adventurous

Wait for a plumber. It will limit your liability.