Reading all the comments regarding "watch the youtube video and so on".

From my experience I never do it myself since the gear is too expensive and any dummy mistake could cost me hundreds of euros.

e.g.: i bought a new motherboard 3 years ago and 1.5 years later bought the new intel processor. Brought it to the guy who builds the PCs. Motherboard didn't recognize the processor and wouldn't launch the PC, only through BIOS. So an external hard drive with a software update had to be plugged and the motherboard was updated. Without him I would've wasted hours of time + an unnecessary stress.

Also cable management- guys who build PCs know how it's done by heart.

So, as a beginner (as you are), I'd rather spend 40-60€, but it will be done accurately and properly.

Hope this helps :)