@VanJosh well a barrier is by definition something that blocks things out or separates things.
depending on how OP you want to make it, it could deflect light , makeing you invisible and make illusions and MUCH more.
because he can ALSO move his barriers at will, it can work as some kind of pseudo telekinesis, like some kind of invisible arm as he is "pushing" the thing with barriers.
but this also unlocks the potential for it to be a even more broken ability.
this would all be fine if he was limited in his use, like for example NOT BEING ABLE TO USE IT AS TELEKENESIS
(which in itself also can be crazy broken if you dont have limits to it, who says you can lift the earth and throw it into the sun for shits and giggles?)
on the other hand if you make it a stretch and go REALLY far down the rabbit hole you could even make it deflect concepts or immaterial things like magic to make anti magic fields or stuff like that.
you need to have limits to how far your power can go, becouse if you dont even a basic power like " createing fire" can be broken beyond belife ( see "release the witch" for more info on that )
another example of powers becoming ridiculous when going out on a limb and don´t limit it was a serie i read a while ago where the MC had a sword with the power to "eat anything".
so he used it to eat wounds to heal people , or eating only dark magic to cleanse them of curses.... you see how thats a problem when you dont limit the powers ?