When do I have to tax profits?

I'm 13 and I do everything possible to earn a little pocket money, which can range from painting the garden fence to mowing the lawn to selling Fortnite accounts, when do I have to pay taxes and how do I do that? Is it allowed to earn pocket money at this age?

With the little things I would not mention that anyway, who should control that?

Yes, just wanted to ask, no desire that a warning or something will come at the end.

If he gets an estimate:-)

But no, joking aside, I think nobody will be interested in you.