In English we make a difference between finished and unfinished time. When thinking of the past we must think about the time in which the action happened.
When we talk about a past action in a past time, we use the past simple. When we talk about a past action in an unfinished time we use the presesnt perfect have / has + past participle.
The uses of the present perfect are
1. To talk about a past action in an unfinished time - I have drunk two coffees today
2. To speak about an experience at an unspecified time of the past - I have been to America
Here you can find a list of irregular verb forms
https://www.englishclub.com/vocabulary/irregular-verbs-list.htm
Irregular verb forms can be hard to remember. You can try putting them in groups of verbs that change in the same way.
Try these worksheets
or watch these videos