Thank you. So I gonna attacch here the letter when will arrive! I don’t know what to do

Mate, sorry I didn’t explain it very well. First of all was my first time and never will happen again ( on a side I am happy, it happened) Second thing they used this words and aswell made symbols with the crossed hands. Security was rude, people told me I could start run. But I am worried how much will be the amount they told me, no idea 500-600

Hi guys, I am worried and I am looking for help. Me and my cousin were caught stealing in primark for an amount about 50 pounds together. They didn’t call police. They just told us we will receive a letter with an amount to pay. They defined it Fine. If we will not pay it they will send our document to the police land will arrest us for 48 hours. And we will add to criminal records. I am asking for help to understand what to do when we will get the letters. Also they told us that we will get the same letter and the amount t that will show on it it will be splitted in me and him ( for example 300 pounds, we need to pay 150 pounds each. ) Is that true? Or it si 300 each? And also ? Should we pay? I am really worried because lots of my friend told me to pay, but I read lost of posts here where no one has paid and nothing happened. Waiting your answer thank you!