Normally you only connect one fan to each fan connection on the motherboard. Each fan connection on the motherboard should be identified in the owner's manual that comes with the motherboard. There may even be a diagram in the manual.
Make sure you connect the cpu heatsink fan to the cpu fan connection on the motherboard. That is a mandatory requirement for pc operation.
Normally the cpu heatsink fan and the case fans are pre-wired. I took a look at the photos of the case you selected. I could clearly see the 120mm fan on the rear panel was pre-wired and had a standard fan cable connector. You should not need any cables or connectors. It should be a simple plug and play.
WR2 - Thanks for catching that! I didn't see it in the photos.