Q: How can i see who are those connected to my hotspot?

Since nothing can connect without knowing your password, & the use of a password is required, you should already know this.

Agree that the password is required.  But while using my laptop in the car (I was not driving !), I had the status "2 connections".  So I'm wondering what other device was connected, especially on the highway.

Is it possible that when another device is trying to connect that your phone shows as one connection, even though the password is not yet entered?

I get a similar thing in the office, which is more normal since a few devices may be around.

The issue is not the password protection. I know I can reset it but I have a few people at that I gave access to connect through my hotspot. However I would like to see who is connected. Is there a way of seeing this ? An App maybe?

That's not what the person asked. Did you even read the question? I've had this happen to me where I've never given out the passcode and then I have 2 connections showing on the blue bar, me and another UNKNOWN connection. There are people called hackers or whatever the **** they call themselves now and despite a passcode they still manage to get through. So I'll ask the same question using different words just in case your brain is incapable of interpreting the OP's question; is there a way to identify the name of the UNKNOWN that is making a connection to my iPhone's hotspot?

Nice point of view.  Why do people too often answer questions other than the one asked??  Thank You