Advice is a noun. It means a suggestion for a beneficial action or decision. A noun is a thing, so advice is the actual suggestion or idea you are offering to another person. An adviser, who is a person (also a noun), gives advice (idea, or suggestion), a noun.
- The student received advice from his school counselor and his older brother.
Since advice is a noun, it can be described by an adjective, as in academic advice, medical advice, or useful advice, We hope advice is useful, but it could also be terrible, so be wary of those who offer unsolicited advice.
Advise is a verb or an action. It means to give advice or offer help.
- The high school counselor advises juniors and seniors on academic, college, and scholarship issues.
The counselor is doing something (a verb).
Here’s some advice (noun, thing, idea) on how to remember. Substitute the word in question with assistance or help (both nouns):
She asked for help (advice).
I offered assistance (advice).
If the sentence sounds correct, then advice is the one to use.
Use the same method for finding the verb form. Substitute with to assist, to help, assisted, helped (all verb forms):
I helped (or advised) my friend on what to do about her teen son.
If the sentence works, then advise is the one to use.