During The Force Awakens, we find out that
Kylo Ren was once Luke's apprentice before going over to the Dark Side.
Until we discover
Rey is also a force user,
are Kylo and Luke thought to be the only remaining Force users in the Galaxy?
So there are some known (to us) force users. Leia, Snoke even Maz at least.
In universe it would depend on who you are.
Most of the general public
Would not know if the Jedi really existed. Luke Skywalker is a legend. The force is a little known religion. Kylo Ren seems little known, even if he was he may not be a known force user.
Someone with intimate knowledge of the Resistance and First order
Consider Lor San Tekka for this point of view.
He knows of Luke and Kylo Ren. He is also likely to be able to assume that there are a number other people with force affinity who have been born, since the empires purges, but not trained (or awakened).
He may or may not be aware of Leia and Snoke being force sensitive.
Trained force users
Every other force user seems to be aware of the others we know of. Leia knows Kylo Ren is still alive. Snoke knows Luke is.
It has been shown a number of times that using the force creates a disturbance. Vader and Palpataine could sense Luke once he started using the force. Snoke and Ren can sense Rey.
So they would be very aware of new force users. If there were others who were actively using the force (and not masking it) it would become very obvious.
The fact that Rey's awakening is so clearly and quickly noticed shows that there are unlikely to be many (if any) other active force users in existence.
As Snoke makes clear that Luke is the last Jedi.
I doubt it because