can't progress any quests without sulphite?

I had the quest to go on the first delve, but i died two times and now i have no sulphite to try again. I don't see any other way to progress in the quests either. In some guides they say to craft flares, but i don't think i have unlocked flare crafting yet.

Are my only options now to either create a new character and try again from the start or quit poe?

Just keep playing the game, eventually you will find Niko again. Don't worry about the quest, it is not essential.

All quests seem to require me to go to an areas that are beyond the mining node. I Would just keep playing the game if i could find any part of the game i would have access to play.

Return back to wherever you were in the campaign (probably Act 4).

You'll eventually encounter Niko again randomly as you progress through the main story, which will provide you with more opportunities to collect Sulphite.

delve is optional. I didn't even do that quest until like level 95.

Ok, thank you, everyone! Since you said that delves weren't necessary to progress, i cleared all my accessible areas in act 4 again and realized that mines are delves are different and there was indeed a path forward in the mines.

It is a little confusing having these quests on the quest bar for new and returning players I think. I remember trying to complete betrayal mission in act 9 thinking I needed it to progress at some point, with the side area.