Are there any rules of thumb for finding the nether fortess, trying to complete a run but i am really struggling with this? help would be greatly appreciated

Rule of thumb. Always go east or west. (i.e. Positive x or negative x in F3)

Depends what version you're in. They've changed nether fortress rarity in the new nether, so if you run 1.16 it is very rare to find a fortress. My preference is to check for open areas where you can see far away, in hopes that you will see a fortress somewhere out in the open. There are a couple other strategies that may or may not be better, but again, it's just preference. If you want a more in-depth explanation, I would ask on the discord.

go towards the open and if u can go open in every direection go positive positive

Alright thanks guys

Ya I think they can only spawn on the x axis so go in whichever x is open

Ya I think they can only spawn on the x axis so go in whichever x is open

It is also preferable to avoid biomes like the soul sand valley, as it can be quite difficult to traverse due to the high amounts of ghasts and skeletons. However, if that is the only open direction, I would go that way regardless.