Questions I can't answer myself

NOTE: I notice this may not be the correct area for this discussion, but in all flat truth, I only need handful of answers and I don't believe I'll be an extremely active user. If it needs to be moved, just let me know.

Anywho, while I'm being flatly honest, the truth is I am basically trying to build more of a modpack instead of an individual mod BUT all within one large mod. Long story short, I'm taking a fair amount of free mods, editing as i see fit with the end goal of compressing multiple mods into one, and keeping it for my own pleasure

The mods I want to pull into one would be:

Tinkers Construct (And about 20 or so add-ons)

Chisel

Wireless Redstone

Additional Structures

Conquest Reforged

and probably more down the road but I don't have a lot of coding experience so I don't even know if it's possible. I would love to be able to make this MPM and if I can do this, who knows what else I could do....

Where do I start?

How do I open these files from multiple mods into one workspace (Eclipse or MCreator)?

How can I get it so Tinkers Craft and Constructs Armory are together even tho they have their own library dependencies?

What is this "illegal state exception" and should I be ready for police at my door?!(okay, yes, slight joke... but i am a bit scared ill have to pay consequences for something that isnt breaking any LAWS as far as i am aware.)

What questions should i even be asking??

Any answers are welcomed, leave them here or message me or whatever. THANK YOU FOR YOUR TIME ^_^