syntactic analysis - I have four children - Simple Present Tense or Something else?

I'm studying english and have been reading about Tenses.

It is my understanding that Perfect tense sentences use HAVE, HAD or WILL HAVE as auxiliary verbs. Some examples of different tenses have been given to me and the following one in particular has be quite confused;

I have four children.

I don't think HAVE is an auxiliary verb in this sentence. I think it is the main verb, in which case there is no auxiliary verb here.

My gut tells me this sentence is an example of Present Perfect, but it doesn't follow the rules. I this instead an example of Simple Present, or something else altogether?

Your help is much appreciated.