I'm not sure how you got introduced to this platform, but if anyone is interested in sending you BTC, they can send it directly to your address.
He probably got a spam message from a stranger/scammer in one of those social messaging apps like telegram or discord
OP, the exchange is a scam. Avoid it at all costs.
They claim that their platform was created in 2021 and has one year experience, but this is not true according to whois domain database.
Domain: linbtc.com
Registrar: NameCheap, Inc.
Registered On: 2022-08-22
Expires On: 2023-08-22
Updated On: 2022-08-22