How to make manual "identification" of users in a chat bot?

Question

Bots

Hello!
Tell me how to implement the idea: the user launches a bot in Telegram. Then he needs to enter a certain code, which he receives elsewhere and not in the bot (each user has a different code). The user enters the code and receives a message that they need to wait for verification. Next, we manually check the conformity of the code. If it is correct = the bot menu opens to the user, if not = an error message.

Ideally, implement this in some kind of constructor, without programming.

Answer 1

I implemented it through checking the phone number, in addition, you can attach an SMS check. The cart has a "Request contact" function and with such a request, the user can send only his contact (respectively, only his phone number).