Soling Dungeons
So, if you are trying to solo a dungeon you won’t have a single build that will let you do it.
What you should do is have several builds. One for stealth to quickly and safely skip as many trash mobs and fights as you can (you can watch videos to see what you can and can’t skip in each path). You’ll then need a build to actually fight the bosses with. Ideally it should have decent uptime on protection, in case you can’t dodge all of the attacks. And you might need several different builds for the different fights to help deal with each specific encounter more easily
What OriOri said.
Basically to solo dungeons you have to use every advantage at your disposal. This means knowing the dungeon in and out, knowing your class in and out, buff foods and consumables and the different specs required for different parts (especially parts which you skip).
If you expect to pick 1 build and run through every dungeon without problems, prepare to be disapointed. Otherwise I guess watching some solo run videos on youtube and mimicking what those players did might be a good place to start. I’m pretty sure by now just about every dungeon has been soloed by every class, fractals too.