I have made a bot with BotFather and got the access token. What I want is to add my bot to a number of groups(I will provide the invite link to it) and it should be able to join the group through an API. So, let's say I have a list of 100 public groups with their invite link, then my bot should be able to join them, this process should be automated. 
I tried searching the telegram API docs, but I wasn't able to find there. Also, the questions on StackOverflow mostly helpful when I want to add the bot to my own group, which I don't want. 
I just want a direction, maybe a function from telethon or any other client. I will then be able to do it by myself.
Only an admin of a group or channel can add the bot. The bot itself cannot add it anywhere. Even a user have to initiate the interaction with bot first.
How to add a telegram bot to different groups with python?