Hey, i just joined this website yesterday. this morning when i open it, there's 6 person who liked me. But to see them i have to buy coins. Is it real or it's just an marketing strategy ?

It's real. The general strategy is to basically like a bunch of people and if they like you back you can talk to them, or you can send 5 nudges, or messages per day I think. There is another thing where they message you or are "online nearby" and that somehow triggers the ability to message them.

Also, if you happen to go into verification status in the first couple days and you are following the rules, just send a message to support to clear your account, or your chatting partner's account, if one of you gets suspended in the middle of a normal conversation. It can be confusing because general message will claim that a bunch of people complained about you when no one actually did. If your chat partner goes into suspension, you will know because you will suddenly lose the ability to message them, and they will disappear from your message list. They will usually clear the account by the next day, provided you contact them and explain the situation.

Be careful not to spam people though. Just try to send the same amount of words back to them that they send to you. That is my general practice and seems to work okay. So far I haven't really had anything serious develop, but its still early on in things for me. Only been here a few days.