Mac drivers for a Dell monitor?

Monitors don't have Mac drivers. You just plug it in and use it.

If 4K is your goal, then you must use the DisplayPort or mini DisplayPort connection. That's the only one that can carry that much resolution. And it can't be a kludge. Like DVI on the Mac and converted to DisplayPort on the other end. You'll still be limited to DVI's highest resolution and refresh rate.

And of course, the video hardware in your Mac must be able to support that high of a resolution to start with.

Did you check on Dell's site? https://www.dell.com/en-us/shop/dell-28-ultra-hd-4k-monitor-s2817q/apd/210-ahiq/ monitors-monitor-accessories

You won't find any.