everything works fine until i actually try to use the CTRL + SHIFT+ I function and then i get this:
Error while running event fluid_permutations::next-ingredients-fluid-recipe (ID 138)
fluid_permutations/control.lua:53: attempt to index a nil value

the recipe in question was making sulfur.

I will look into it.
In the meantime, could you provide a bit more details.
Do you have other mods? Which ones?
Are you playing in normal or expensive mode?

Edit: Also if you are using other mods, on what building does this happen?
And what version of Factorio are you using?

I am new to using mods in factorio however my mod list is rather long, is there a quick way to get you a mods list or do i need to type them out? i am on version 0.16.51 playing in normal mode but not campaign and the machine is the chemical plant.

If you know where your mod folder is, it contains a file called "mod-list.json", it contains a list of all the mods you are using. Or take a screenshot of the contents of the folder.
Could you take a screenshot of the ingame tooltip when hovering over the building. Like this: https://i.imgur.com/xFLWEoW.png
and the recipe (like this: https://imgur.com/nWU87Cg.png )
The important part is the yellow text.
Or alternatively you could just give the me text.
If you are more comfortable with discord, you can find me on (the factorio) discord @infinite_zero#9426