Hi how are you? Well, it's a little complicate. Usually this tense is used to describe an action that is occurred in the past (minutes, days...in the spoken language doesn't matter). You build up the tense using:
1. First place auxiliary verbs "to be" or "to have"
2. Second place the present perfect form of any verb (ex. seen, gone, told, and so on)
Remember : NEVER separate the auxiliary from the other verb, it's considered a big mistake
Do you know the declination of "be" and "have"? You have to decline them according to the person ( I, You, He/She/It and so on), while the present perfect is declined according to other rules ( singular or plural/masculine or feminine).
Past perfect sometimes does not change, it dipends from the verb
Here some examples:
1. They went to the shop
ESSI SONO ( auxiliary verb " to be" declined for masculine plural) ANDATI (past perfect for masculine plural) AL
NEGOZIO
2. You went to the train station
TU SEI ANDATA ( this is for feminine singular) ALLA STAZIONE DEI TRENI
You have to learn when to use BE or HAVE from a good grammar book, or from specific lists... it's boring but otherwise another good solution could be finding italian friends and speak a lot with them ;) Good luck