"Best" is relative: price, performance, etc. all need to be quantified.
I am not aware of any dongles that do both Wifi and Bluetooth.
I am aware that there seem to be problems with some Broadcom based USB Bluetooth dongles. Working that as a side matter (personal).
What you will need are the applicable drivers for the dongle with respect to both Debian Linux and Windows 10.
Starting checking the manufacturer's websites to ensure that they have the applicable and functional drivers. Also visit the manufacturer's Forums and FAQ's to see what problems are being reported and discussed.
All too easy for manufacturer's to make claims. Look for end user verifications.