As others have stated, drivers are attained from the manufacturers website support page for the particular part needing drivers. As said, Windows will install mostly generic drivers and get you running but to get the performance, you'll need the proper drivers.
So once you've assembled the components into the case and assured it's all running and have a display, can enter Bios etc. Plug in the USB stick configured by Windows Media Creation tool and set boot priority to USB and restart. USB boot can sometimes be automatic or a button need to be pressed to proceed.
Once in the install process, you'll want to do custom option and wipe the destination drive as explained in this video and also the guide here at Tom's. Make sure to back up your personal files / Steam games etc if you don't want to download them again. Other installed programs will have to be reinstalled afterwards.
See video. Custom install option starts from roughly 4:00.
After Windows is installed, depending which motherboard you get, google search the motherboard model and the website should popup. Head to the support page and look for drivers. The main drivers are usually Chipset, Sata, Audio and Lan. The APU driver you can get directly from AMD, just search Ryzen 5 2400G driver. Motherboard websites offering APU/GPU drivers are often out of date.
An example. If i had an Rog Strix B450-F Gaming motherboard and wanted drivers, i'd search the model name and results will give me
https://www.asus.com/au/Motherboards/ROG-STRIX-B450-F-GAMING/ Then i'd go to support > Driver & Tools > Select OS and drivers will be listed. Website layout isn't exactly the same across all brands but do follow a similar standard.
Be prepared for Windows not to activate though, as i said earlier. A new motherboard replacing an OEM Pre-Built PC tied to the current licence will usually result into neeing to buy a new license, which costs around $100. Can run Win10 for free however with some limitations if need time. Playing games shouldn't be affected, it's more to do with personal preferences and cosmetic side of things. And an annoying water mark at times.
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One more thing. Before installing Windows 10, disconnect all secondary drives except for the destination drive where you want Win10 installed to. It has a habit of putting boot files on other drives if connected and if, for whatever reason, you removed the unsuspecting drive containing the boot file, you'll be scratching your head wondering why Win10 is failing to boot. Connect your other drives back after everything is done.