I want to add a property based on currently logged in user id or just help me to access the currently logged-in user id.
Get the currently logged in user id (generating dynamic url with respect to currently logged in user)
It's not currently possible to get the currently logged in HubSpot user, and there isn't currently any support for session-based or user-specific authentication. If you have the inclination, I would encourage you to check out the Ideas Forum on the HubSpot Community. There, you can create a post including your use case that product and other customers can see.