There are two ways to join a Remote Support Call:
First is to receive a direct link, that when clicked, which will prompt you open the App (you must have the app installed), and once the App is opened you will be directed automatically to the room\call that generated the link.
The second way is to manually insert "ID" and "Password" the following way:
Opening the App
select "Remote support"
select "Join room/meeting"
insert ID number
Insert password (if needed)