Advice and advise are related words with related meanings.
Advice is a noun that means "an opinion or suggestion about what someone should do."
My advice is to sell your old car and get a new one.
She's been giving him some expert advice about investing.
I lost some weight on the advice of my doctor.
Advise is a verb that means "to give an opinion or suggestion to someone" or "to give advice":
I strongly advise you to sell your old car.
She advises the President on foreign affairs.
We advised them to save their money.