It is used to expressed an action which happened or completed in past but usually the action which happened or completed at a short time before now (near past) not a very long time before now.
Rules: Auxiliary verb “has or have” is used in sentence. 3rd form of verb (past participle) is used as main verb in sentence.
We use the present perfect tense:
1.For something that started in the past and continues in the present:
They have spent their life exploring.
2.For something we have done several times in the past and continue to do:
I’ve read fiction ever since I was a teenager.
He has written three books and he is working on another one.
3.For something that happened in the past but is important at the time of speaking:
She can’t get in the house. She has lost her keys.
Tanya is at home. I think she has not gone to office.
4.In questions and negatives with so far; until now; up to now; yet.
Have you ever been to a beach?
Has he finished his homework yet?