Computer for gaming and office

Hello all,
After 8 years it can become a new computer.
The main focus of use is office and surfing (about 80%). However, I also like to play from time to time and want to get my money’s worth.
I also find the topic of virtual reality glasses very interesting. I have an Oculus Quest 2 – standalone glasses that can be attached to a computer using a jumper cable. I’ve never done this before because my computer was too weak to make sense. With a new computer it would be an option.

To the questionnaire:

1. Do you want to play on PC?

• What exactly are games? …
• You have played a lot of RPG recently, for example Kena – Bridge of Spirits, Edge of Eternity, The Witcher, Forgotten City; But he also likes racing games, action adventures or development strategies (the latest being Jurassic World Evolution), and, as I said, sometimes VR games with Quest 2.
• Accuracy + detail etc. to the highest possible level with budget

2. Would you like to use your computer to edit photos/music/videos or CAD? As a hobby or are you a professional? What software will you use?

No or at most in the lower hobby area

3. Do you have any special requirements or wishes (overclocking, a particularly quiet PC, RGB lighting, …)?
RGB please no. Quiet is, of course, fine, but it doesn’t have to be inaudible. OC is not intended.

4. How many screens do you want to use? Number, Model, Resolution, Refresh Rate (Hertz)? Do you support FreeSync (AMD) or G-Sync (Nvidia)? (Please include a link to the manufacturer or compare prices!)
I currently have a Dell U2412m, ie 24 inches 1920 x 1080. But then I’ll swap it out for a higher resolution. If you buy a new monitor today, it’s better to use 4k, right? Do you have any recommendations?

5. Do you still have an old computer, some of its components can still be used? (Please with links to specifications from the manufacturer or compare prices!)
You have installed BluRay burner. It wouldn’t be bad if I could handle it (although I never needed it…so it wouldn’t be an absolute necessity)

6. How much money do you want to spend?
Including the screen, I will spend up to 2500 euros.

7. When do you want to buy the computer? Immediately if possible or can you wait a few more weeks/months?
By itself there is no rush, but I’ve been saying that for about a year… Prices don’t seem to go down for the foreseeable future anyway? “Wait” is always said, or is there a special reason for that?

8. Would you like to assemble the computer yourself or assemble it (by the store or by volunteers)?
Put them together. I assembled the last computer myself, but I swore and swore I wouldn’t do it myself next time.

I am grateful for the suggestions!