I have using an assembled pc which ia had assembled few months ago and its working like a beast computer. Its very easy to assembled a PC as your requirement and your need and the happiness will be great when you use your pc assembled by you. You will find lots of tutoriala on youtube to assemble a PC but before buying its stuff I give you some quick tips to make your own PC.
You nee some parts of a PC to assemble, You can choose as your requirements and all the parts and motherboards have clue of its wiring pins and ports so its very easy to connect.
Here are some great tips for building a massive powerful PC.
First of all you need a motherboard, Its a base of your PC. All functionality of your computer that means processor RAM, Graphics depend on it. Choose a motherboard furture proof so you can upgrade as per your requirement in future also.
Second thing is to choose in precessor for you computer. Choose a processor which should perform well. You can choose between intel and AMD, both processors are the best now a days.
Choose a memory for your computer that is hard disk. At least 320GB of hard disk is a must for you computer to store the data. As per your requirements you can choose up to 1 or 2 TB hard disk.
Nest thing to choose is RAM for your computer to run all the programs and processor and all the system of your computer. At least 4GB of RAM should be adde . You can choose RAM from brands like Kingston or Transcend, These are best.
Then come at the graphic card for your computer Graphics card is vey inportant to playing games. watching high quality vedios, but if you dont want this then in built motherboard graphic is enough for you.
You will need a PSU also, that is a power supply for your computer, choose it according to your configuration. Brand like EVGA, SEASONIC, CORSAIR are best in that.
After all this choose a monitor according to your need with futurstic 4k so you can use it for many years.
After all these major parts choose other stuffs like cabinate, mouse, keyboard, etc. As your choice and these all parts which I mention above comes with manual guide so no need to worry you can assembled whole PC reading it its so easy.