Bootcamp DAI on Mac + upgrade windows 8 to windows 10

Okay, so I've wanted to bootcamp windows on my computer for quite awhile now, mostly because there's a lot of software that isn't available for mac... including Dragon Age: Inquisition.

I bought Parallels, which sucked.  It was awful.  I was told that it wouldn't be a problem with my processing speed, but when I opened windows it was weirdly blurry and when I played Dragon Age it was stuttering and choppy the whole time.  Unfortunately, you can't return Parallels, and I don't know if it can ever be used again once the activation code was used.  So... if anyone wants a potentially completely useless version of Parallels, let me know.

So I've decided to try bootcamp (which I was stupid enough to not use in the first place, because I have Yosemite and for some reason windows 7 doesn't work on that) and traded in windows 7 for windows 8.  I've heard that windows 8 is absolutely awful, so I was planning on getting the "free upgrade" for windows 10, but I have no idea if that would even WORK using bootcamp.

I have a Macbook Pro with these specs:

• 2.5GHz quad-core Intel Core i7 processor (Turbo Boost up to 3.7GHz) with 6MB shared L3 cache
• Memory: 16 GB 1600 MHz DDR3
• 512GB PCIe-based flash storage
• Intel Iris Pro Graphics
• AMD Radeon R9 M370X with 2GB of GDDR5 memory and automatic graphics switching

If I missed anything, here's the link to the specs.  It's the last one on the right.

In order to run Dragon Age Inquisition, these specs are required:

Minimum:

• OS: Windows 7 or 8.1 64-bit
• CPU: AMD quad core CPU @ 2.5 GHz; Intel quad core CPU @ 2.0 GHz
• System RAM: 4 GB
• Graphics Card: AMD Radeon HD 4870; NVIDIA GeForce 8800 GT
• Graphics Memory: 512 MB
• Hard Drive: 26 GB
• DirectX: 10

Recommended:

• OS: Windows 7 or 8.1 64-bit
• CPU: AMD six core CPU @ 3.2 GHz; Intel quad core CPU @ 3.0 GHz
• System RAM: 8 GB
• Graphics Card: AMD Radeon HD 7870 or R9 270; NVIDIA GeForce GTX 660
• Graphics Memory: 2 GB
• Hard Drive: 26 GB
• DirectX: 11

I want to be able to play this game.  It's not the only reason I bought windows, but I still want to be able to play it, I'm just not sure how to make that happen without it being choppy and laggy and basically unplayable.  I haven't installed anything yet, since the last time I did turned out to be a disaster.

So basically

1. Can/should I install windows 8 on bootcamp and then upgrade to windows 10
2. Can my mac even run Inquisition appropriately
3. How much "space" (I am so sorry.  I can't for the life of me remember what it's called) should I give to Windows?  I won't be able to change it after that, so all of that... whatever its called is gone from my mac and will presumably make it run less smoothly/slower.

Sorry this is so long and complicated!!  I appreciate any help at all, thank you!!