Telegram has heavily participated in misinformation campaigns targeting actual private messaging apps with always enabled, properly implemented end-to-end encryption such as Signal. Should stop getting any advice from anyone who told you to use Telegram as a private messenger.
Telegram is capable of handing over all messages in every group and regular one-to-one chat to authorities in France or any other country. A real private messaging app like Signal isn't capable of turning over your messages and media. Telegram/Discord aren't private platforms.