Would this pc build work i never built a pc before and should i use a water cooler for the cpu the parts i want to use are cpu

If you're looking to play all the latest games at 4K, you're going to need some serious processing power. And that's what this builds, delivers - every component has been selected with one and only one goal in mind: maximum high-resolution performance for $2,500!

CPU:
Intel Core i7-5820K
With Intel's six-core i7-5820K, you get an unprecedented amount of processing power for under $400 - a price lower than the quad-core i7-6700K.

MOTHERBOARD:
Asus X99-A/USB3.1
Based on the cutting-edge X99 chipset and packed with functionality, the X99-A is the board of choice for this build. Using a patent-pending socket design to allow for higher overclocks than competing boards.

VIDEO CARD:
EVGA GeForce GTX 980 Ti Hybrid 6GB
One of the best features of the GeForce lineup is G-Sync, which matches framerates to the frame output on compatible displays for stutter-free gameplay.

MEMORY:
Corsair 4x4GB Vengeance LPX DDR4-3000 Black
The X99 platform requires the use of new DDR4 memory, which offers very high frequency and low operating voltage.

SOLID-STATE DRIVE: (optional)
Samsung 850 Evo 1TB
Given serious price cuts on the new Samsung 850 EVO 1TB drive, there's just no question that it's the right pick for this build.

HARD DRIVE:
Toshiba 3TB
Hard drives are pretty utilitarian at this point and it's high-quality drive and best in market.

CASE:
Phanteks Enthoo Luxe White
Phanteks made its name in high-end CPU coolers.

POWER SUPPLY:
EVGA Supernova GS 1050W
Designed for EVGA by none other than Seasonic, the best name in the business, this 1050W unit comes in at around the same price as other less-impressive models.

CPU COOLER:
Corsair Hydro H100i GTX Liquid Cooler
With a six-core CPU under the hood and lots of hot air being exhausted into the case by twin video cards, you're going to need a CPU cooler that can cope with a lot of heat. (**and for your concern for water coolers thay are definetly safe and best option for cooling**)

OPTICAL DRIVE:
Samsung SH-224FB 24x DVD Burner
While there's not much to distinguish DVD burners nowadays, this model comes from a company everyone knows and trusts.

OPERATING SYSTEM:
Microsoft Windows 10
Windows 10 is here and it's a huge improvement over Windows 8.1, feturing their new software cortana.

they all end up in less then 2500$ all of these can be found on newegg.com. Have a nice day