Hi
Kshara karma is done for interno external piles (and many other diseases) and Kshara sutra for Fistula in ano, pilonidal sinus etc. Cure of hemorrhoids, anal fissure can be achieved only through proper treatment followed by good Diet and Lifestyle on a regular basis.
Next Steps
You can go through my YouTube video(s) for more details
https://youtu.be/jtHv68JqkfI
https://youtu.be/oXDVIP2BLKI
https://youtu.be/MO4ZmWiz6YM