Not so fast! You've misunderstood the term a bit. There is nothing wrong with that.
A linking verb is, as you stated before, followed by an adjective or a modified noun. Such verbs are: get, become, keep, remain, seem, appear, and so on.
John should be here (adverb of place) by 2:00 PM.
You should stop eating(gerund) fast food.
I will not be late(adverb of place).
I will be waiting outside(adverb of place).
Those are auxiliary or helping verbs.
You just mixed up their function in a sentence, failing to recognize a linking verb.
However, here is an example of a linking verb in usage:
She seemed weary (adjective, complement).
In some instances, when the adjective starts with "a-", to-infinitive has to be inserted.
She appeared to be alive. ( but not: appeared alive, as it sounds unnatural and incorrect. );
Because it's an adjective preceded by a verb and that adjective becomes the complement ultimately, we can now see how you recognize a linking verb.