You DO NOT have to "Connect" with another User/Patron to "Help" them, I help others from all around the World all the time; and, I do not "Connect" with them.
You just need to know (ie. be told) the 'FamilySearch Person Identifier' (PID) of the "Deceased" individual/person the other User/patron is researching.
We can ONLY 'see' "Deceased" individuals/persons in "Family Tree" of 'FamilySearch'.
We CANNOT 'see' "Living" individuals/persons in the "Private Spaces" of ANOTHER User/Patron in "Family Tree" of 'FamilySearch', NOT even immediate Family members.
IF, you are a Member of the Church; THEN, there are some additional options.
I hope this helps.
There are billions of records in FamilySearch Family Tree
and you have access to all of them (not just your own family) - just like the rest of us also have the same access.
You can bring up any family tree in FS FT
just use the find screen to query for a specific person.
(assuming the persons are deceased)