Hello Abdul
Yes, this is an important clarification that you are asking for. Regardless of RSTP, in general terms, a point to point interface is one that uses a point to point technology, such as a serial interface. On such an interface, only one single device can be connected on the other end of the circuit. Conversely, Ethernet is not considered a point to point technology, but a broadcast technology, because you can have multiple devices on a single network segment.
Looking at these terms within the framework of RSTP however, these terms take a different meaning. Specifically, a point to point connection, as far as RSTP is concerned, is any connection on the interface of a switch. Because switches create a separate collision domain for each switch port RSTP considers such links connected only to a single device on the other end, thus a point to point link.
Conversely, if you were to use a hub (bad idea by the way), then the link to a hub would be detected by RSTP as a shared link type. Such a link would not be able to be placed immediately into a forwarding state by RSTP.
I hope this has been helpful!
Laz