Teaching on the coLanguage platforms means you work as a freelancer. To declare taxes is your own responsibility according to the requirements and legislation of your own country.
Depending on your legal status, you will need to create invoices with or without VAT. You may also be able to use the reverse charge system for VAT.
You can find our legal company information here.
Your income as a teacher is income from self-employed work. You don't have to register a business, but you have to correctly declare your income in your annual tax statement.
In order to keep your accounting correct, you should create invoices to us. Here you will find our company information.
For further questions, you should ask your accountant.