You've done a lot, but we'd need to know the actual error you get when you run your bot code or try to use it. You only listed out the general steps you've taken, so there could many problems at any of the steps. As a rule of thumb, you'll need to get every individual part working on its own before you try to link them together.
That means validating the telegram and openai apis separately, making sure they both work. Then going in and linking them up to build the bot.