In a telegram channel via python, I need to add texts that subscribers write to the variable, how to do this?

Question

Python

For example: Ivanov sent the word hello, I have to check this word, compare it with something and send the answer to the same channel.

I tried to do it with a telegram bot, right in the bot, but it didn’t work, because I use a cycle, I count the database, I check it, i.e. when using bot.polling (non stop=true), the cycle stops working