> Anyway, that's a site where you register to report and pay taxes.

No, it's a government website where you generate invoices so that other people can pay you for services rendered. Every businessman needs to deal with this bureaucracy.

> It's not something other people will rush to do in your name.

Anyone who impersonates me and gets into this system could launder money through my business.

You need a digital certificate to generate invoices.

The worst an impersonator who got into this system could do is see all of the invoices of services provided to you or your business.

Which is also bad, but not nearly as bad.