The verb "have" is one of the most important verbs in English. It can be a main verb or a helping verb. It can be used in all different kinds of tenses, and it can be very idiomatic. Here are some examples for the different ways to use the verb "have."
As a main verb
I have a big appetite.
Do you have anything to eat?
What are you having for dinner?
How much time do you have?
Aimee has a stomach ache.
We had a good time last night.
The Nelsons have three cars in their driveway.
What kind of furniture does Jenny have in her apartment?
Charles has on a red shirt and jeans today.
Yolanda had a great job until she lost it.
As a helping verb
The verb "have" is a helping verb for perfect tenses:
How long have you lived in the United States? (present perfect tense)
I had never heard of that before until you told me about it. (past perfect tense)
By this time next year, I will have completed 20 years at my present job. (future perfect tense)
I’ve got it.
As an infinitive: to have
What do you want to have for dinner?
Tom would like to have some friends over for a party.
We need to have more time to get this finished.
As a gerund: having
Having children is one of life’s greatest pleasures.
They never get tired of having people visit them.
The cat likes having a big sunny window to sit in front of.
As an idiomatic modal verb: have to
Jacob has to go to work today.
The students have to finish their assignments.
What do you have to do today?
The city has to cut back on spending or raise taxes.
As a causative verb
We had our house painted last summer. (Someone else did the work.)
Do you have your taxes done by an accountant?
Our neighbors have their house cleaned by a housekeeper.
As a form of slang
I’ve had it. (I’m not happy with this.)
Let’s have at it. (Let’s do this.)
You’ve been had. (Someone tricked you.)
Is that all you have? (Is that the most you can do?)