it's a convoluted install that involves online sometimes.
it's an OK tool but don't buy the hype: it might reject (not load) up to 40% of the isos and they won't load. that's the limitation. Not everything can successfully launch/load from Ventoy, but most isos can.
the health of the storage usb also a factor in this ^^.
so be prepared for that. But if you get a wild hair and download a crapload of isos and want to go to town, this is the tool for that. Ventoy can be a lot of fun that way.