Jvill40

No, the M.2 on the board and the SSD are incompatible. 

You cannot use the M.2 slot with that SSD. The slot is PCIe only, it cannot use the SATA communication protocol. 
 
That adaptor should work though. It basically converts the M.2 connector from the SSD to standard SATA power and data. It doesn't convert the PCIe M.2 on the board though. 

Should be able to grab a GTX 1060 for roughly $250 then. Performs better for the games you've mentioned before.

The Gigabyte board that you have chosen is a higher end model, when compared with the MSI model that you have chosen.  The MSI Z170A is, by its model name, a Z170 (skylake platform) based chipset and the "A" at the end detonates a "Average" feature set, like Asus has a Z170A model, which is really kinda a "baseline" model.  (Yes, I know the "A" doesn't stand for "average", I just use that as a illustration point.)  Where as the Gigabyte model you have chosen is a Z170X Gaming 3 model.  This model is, just like the previous, a Z170 chipset with a "X" detonator, which I will say stands for "X-treem".  Which means that it will be a bit more bleeding edge, with USB 3.1 type C, probably will offer slightly better power delivery, some kick butt M.4 connectors, and so on.
 
Basically, if you're wanting a "I don't want to fight with it" kinda build get the MSI model.  It wont have any extra frills and has less points for things to go wrong.
If you're going to overclock, or if you don't mind playing with drivers and such to get that "next best thing" to work correctly, then go with the Gigabyte model.

every single motherboard made in the last like 10 years is compatible with sata/traditional ssds because they use the same ports as hdds

no its kinda complicated actualy, m.2 is like a small pci-e port where you plug in ssds (faster than traditional ssds/sata ssds)

Nope unless you plan on going CFX  but you may as well sell your old GPU and get a better GPU when it comes  (but...but...you might be getting 390x/980 performance for $200 so...yeah )
 
Drop the motherboard for something cheaper with 2 PCIe 16x slots (with one being 16x and one 8x so you can CFX/SLI in the future) and get a damn SSD
 
something like this:
PCPartPicker part list / Price breakdown by merchant
CPU: Intel Core i5-6500 3.2GHz Quad-Core Processor  ($194.99 @ SuperBiiz) 
Motherboard: Gigabyte GA-Z170X-Gaming 3 ATX LGA1151 Motherboard  ($136.89 @ OutletPC) 
Memory: Kingston HyperX Fury Black 8GB (2 x 4GB) DDR4-2133 Memory  ($36.99 @ Newegg) 
Storage: A-Data Premier SP550 120GB 2.5" Solid State Drive  ($35.99 @ NCIX US) 
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive  ($47.49 @ OutletPC) 
Video Card: Sapphire Radeon R9 390 8GB Nitro Video Card  ($317.99 @ SuperBiiz) 
Case: NZXT S340 (White) ATX Mid Tower Case  ($61.99 @ SuperBiiz) 
Power Supply: XFX TS 550W 80+ Bronze Certified ATX Power Supply  ($59.99 @ NCIX US) 
Keyboard: Cooler Master CM Storm Devastator Gaming Bundle Wired Gaming Keyboard w/Optical Mouse  ($19.99 @ Newegg) 
Total: $912.31
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-06-06 14:26 EDT-0400
 
(wanted to go h170 as you're not OCing but all of their second 16x slot is only 4x electronically so...no SLI support and you're talking about the future so...yeah plus the gigabyte motherboard is still red and flashy so...hue hue hue)

Future upgrades like? Dual GPU setups? A single more powerful GPU will always trump a dual GPU setup, unless you're are talking about VR, where you might be better off assigning each GPU to each eye.
Or fat triple slot GPUs? The case has 4 PCIe slots so don't worry.
Like @Mr.Meerkat and I said, you're better off getting a better GPU than going CrossFire.
For SSD, you could go either or a combination of:
1) Install OS on SSD, apps and data on HDD
2) Install frequently used apps on SSD, rest on HDD
3) Install OS and most frequently used apps on SSD, rest on HDD
4) Store frequently used data on SSD, rest on HDD
Or use SSD as a caching drive.
 
Yes, you can download your games you play to the SSD, and leave the rest to HDD. It's all about efficiently utilizing the fast, but rather small space.
For transferring data from SSD to HDD, you will be limited to HDD speeds.
 
For monitor, pick whatever you like, but choose a FreeSync monitor.
http://pcpartpicker.com/products/monitor/#A=2&sort=a8&page=1

I think I'll go with the lower tier graphics card now and then try selling it in a month when the new cards come out and I have more $$. When it comes to the SSD, is there a "best" option out of the ones you proposed or does it sort of depend on personal preference/what you're using your computer for. Since it would primarily be a gaming PC wouldn't I want the games I play to be on the SSD and leave the OS on the HDD, sacrificing startup speeds for better game performance? Or would it be better to have the OS on the SSD and then use the increased space of the HDD for all my games. @Mr.Meerkat @Shahnewaz thanks again for all your help so far since I'm fairly fresh into the PC community

Hopefully you now have a clue roughly what you're gonna get , good luck and have fun building your PC  

I think I'll go with the lower tier graphics card now and then try selling it in a month when the new cards come out and I have more $$. When it comes to the SSD, is there a "best" option out of the ones you proposed or does it sort of depend on personal preference/what you're using your computer for. Since it would primarily be a gaming PC wouldn't I want the games I play to be on the SSD and leave the OS on the HDD, sacrificing startup speeds for better game performance? Or would it be better to have the OS on the SSD and then use the increased space of the HDD for all my games. @Mr.Meerkat @Shahnewaz thanks again for all your help so far since I'm fairly fresh into the PC community