So when I try to read online guides/ watch videos on enhancing (updated from within past few months). They show a completely totally different menu from what I have. In particular they talk about "fail stacks" and how I'm supposed to "save them" and not use on naru gear. But the "enhancement chance" is used up automatically when I try to enhance my naru gear. So I don't have any options or buttons to "set aside" that enhancement chance (which I'm assuming is the failstacks because no one is actually using the proper same enhancement menu as me to explain this stuff).  So is there a resource that explains step-by-step the literal current enhancement menu and what it all means and how it works? Cause I don't see fail stacks to option to "save your fail stacks" anywhere. And on recent enhancement guides for new players; I don't see the same menu as me.

There's a quest in the Suggested Tab to unlock the Nadaar band, you can swap a failstack onto the Nadaar band to save for later, you can then swap the failstack onto another character if you like, thereby each character you have can save a failstack, and each Nadaar band can also save a failstack. (There's also an item you can buy from the blacksmith that can save one into being advice of valks).

Just to add, the enhancing interface was recently overhauled with a completely different look so it's likely you could be looking at content that was created before that.