How can I create a macOS bootable usb on Windows 10?

well there are plenty of free options out there so one wouldn't necessarily need to use the pay-to-use program you have suggested. I'm not entirely sure how this sort of "advertising" of a third party program is even allowed on here. Especially considering TrustPilot has a rating of only 2.6 for UltraDMG and that is most likely only even that high because of false reviews stating it works. They are proven to be disreputable in both their functionality as an app and for their customer service (or apparent lack thereof). As a matter of fact, I couldn't even type in the name of the company behind it into this comment as I got a warning stating that "So-and-So is not allowed...". I highly suspect that you are a shill for this company masquerading as a "satisfied customer".

WilliamsMoore This is correct. It could be much easier to create a macOS bootable USB on a Mac with the createinstallmedia command. The createinstallmedia command is a Terminal utility provided by Apple for making a bootable USB installer for macOS. This is especially useful when you need to install macOS on multiple machines, perform a clean installation, or recover a system that isn't functioning properly.

First, set up a macOS virtual machine on Windows PC. Then download the macOS installer from the App Store. The installer will be saved in your Applications folder with a name like Install macOS Sonoma.app, Install macOS Ventura.app, etc., depending on the version.

After that, connect a USB drive and follow the command to create a Mac bootable USB drive on Windows PC for free (taking High Sierra as example):

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

WilliamsMoore An easy way without taking much time is to download the dmg file of Mac OS X or macOS. After that, burn dmg file to USB flash drive with command line or third-party tools. This will format the USB with proper file system and extract content from bootable dmg file. I have been using this trick for creating macOS bootable on Windows 10 for years and no problem with this at all.

The most trick part is how to find a working dmg file on the web as Apple only offers dmg download for a couple of old Mac OS X versions, like El Capitan, Yosemite, Mountain Lion and Lion.