Telegram has always been filled with bunch of scammers, fake accounts and groups. You will find most of the scammers trying to talk to you through telegram. Just don't accept or communicate with anyone random on telegram. Leave groups that you didn't join. If someone on telegram claims to know you (was supposed to add you), verify if its the same person you were supposed to talk to.
I doubt there are any apps that will help you do that. This would cause an issue with user privacy.