And pick up whatever mouse and keyboard you like the look of.
There may be other options for prebuilts with better specs and I dont have that much knowledge of that market. In general for your price range you should be looking at getting :
-16GB of RAM,
-A cpu with 6 cores (Ryzen 2600/3600, Intel 10400/10600) or better
-An SSD makes a lot of difference to the user experience even just for Windows.
-GPU should be a GTX 1660 or above or Radeon 580 at minimum IMO.
-A monitor with Freesync, 120HZ or over is a big plus if it can be done within budget.
Its a fun hobby to build and play with PC's and I really recommend it. If you can wait unril things return to some semblance of normality hopefully later in the year then do. But if you want to play games right now, a prebuit is going to get you more value for money. Though it pains me somewhat to say it.