Help Telegram contacts question

[spman]

Hi,

I think any of my contacts that login to telegram I will see something like this "John joined Telegram" screenshot https://i.imgur.com/O0DzP3u.png

Assume my name is John and I login to telegram today.

1. Will [Delete Synced Contacts] remove [John joined Telegram] message that appeared in my friend phone (friend number is in my phone contacts)?

2. How to prevent "John joined Telegram" message from appearing in my friend phone (friend number is in my phone contacts)?

3. What does [Delete Synced Contacts] in telegram do?

4. Does this "John joined Telegram" reappear in my friend phone (friend number is in my phone contacts) everytime i logout and relogin telegram?

5. Does pressing [Delete Synced Contacts] delete my existing added friend contact and chat history seen in my telegram?

6. Does pressing [Delete Synced Contacts] delete "John joined Telegram" that is already in my friend phone?

Thanks
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I saw some guides on Delete Synced Contacts
https://www.howtogeek.com/711226/how-to-use-telegram-without-sharing-your-contacts/
https://www.techmesto.com/whatsapp-adds-emoji-reactions-support-for-messages-how-to-use/