The verb is a part of speech, and verbs are generally action words. Verbs are words which indicate action, event, and state of things. Verbs are grouped into different parts, we have lexical verbs, modal verbs, helping and linking verbs. Helping and linking verbs are related because they are two types of verbs, but differ when it comes to how they are used in forming a sentence. Linking verbs are verbs which are used to attach the subject of a sentence to another word entirely.
For example, I am cool. The linking verb here is 'am'. One important thing to note is that linking verbs are not action words. Examples are, am, was, were, be, being, etc. Helping verbs, on the other hand, are also known as auxiliary verbs, they are used together with main verbs. On their own, they don't have any meaning, but they add meaning to main verbs when you use them together. Examples are; has, have, had, etc.