Crackers are offering to upgrade my accounts for a little money

In my place in Bosnia, I noticed that through ads they offer account upgrades, primarily Coursera, for about 5 EURO. So he offers to integrate the premium on my account and open all the possibilities for me, it really works. In addition to sadness, there is also Netflix, Disney + and all the others.

Can someone tell me the secret, how he actually integrates the premium on my account even though I only paid 5 EURO. Is it possible, plus it gives an additional guarantee that everything will work