Fans

As a general rule, bigger fans should be quieter. Thus it's best to take the biggest available fan that fits into your case / CPU cooler. Then you can check RPM and decibel (noise) levels.
Fans should be connected to the motherboard. The newer standard is to use 4 pin connectors with PWM (Pulse Width Modulation).
Motherboards may not have enough fan headers. There are cables like the Noctua NA-SYC2 that will solve this issue though. You can also use the pump header for a fan if you only use a CPU cooler fan - it will work.

CPU coolers

A bigger CPU cooler is better but be very careful of the dimensions of your cooler as it needs to fit in your case. A compatibility site like Pangoly should always be used before buying.