When we use the Present Perfect, it means we want to express that something started in the past and continued or is continuing in the present.
To make the Present Perfect, you will need to know the Past Participle of the verb you want to use:
walk - walked
study - studied
am - was
Then, you use has or had before the past participle to make the sentence.
has/had + past participle
She has studied cooking.
He had walked to school every day. (when he was young)
We had attended the training day on Friday.
We use the present perfect to express a change over time. Something that started in the past and continued to the present. "She has grown since I saw her last time", "He has learned so much English since living here". We can also use it to talk about things that started in the past and are still true or relevant now. "She has studied Japanese", for example. She studied Japanese in the past, and she still has the skill now. "He has eaten all of the cake". He ate the cake in the past and there is no more cake now in the present.
Watch the video to see when we use the present perfect tense and for some example sentences. You can also find a mind-map and more information in our write-ups.