I'm wanting to upgrade my GPU from a 1050 2gb ddr5 to a 1060 6gb ddr5. I'm just wanting to make sure it's compatible with my mobo (and will fit in the case, i'm sure that's not a problem though)

AMD A320 AM4 socket type.

When looking up the 1060, I saw this (bolded): PNY GeForce GTX 1060 DirectX 12 6GB 192-Bit GDDR5 PCI Express 3.0 x16 Video Card. I assumed it would fit, but after scrolling down, there was a 1070 with a 256-bit.

Is this relevant to the mobo? I'm still stupid as hell when it comes to comps and trying to figure this stuff out...

Idk where to find the case info, it's a prebuilt computer.

In the vid card specs you will find the length. Measure inside your case. If you have the room, it'll work.

As for the motherboard... it'll work in your motherboard.

the memory bus is completely irrelevant to the motherboard or basically anything in your computer besides the gpu.
ofc it's compatible with your mobo
maybe not the case
but if it doesnt fit case, you can make it fit
i did that once with a reciprocating saw