How to beat Nights Cavalry in Caelid?

I'm trying to beat Nights Cavalry in Caelid and Im having issues at the moment, pretty much every time im dying it's cuz I get too close (the only way I can attack cuz casting spells would probly be too slow) and he stun locks me and attacks me multiple times in a row, knocking me off my horse and killing me

Edit: I'd like some tips for beating the Draconic Tree Sentinel too

Update: I beat the Draconic Tree Sentinel