Launch first startup full-time at 20 years old? Or do an exchange in Australia? Very conflicted so any advice is greatly appreciated.

I have the opportunity to launch my first startup in the Toronto/GTA area. I am confident in my idea and there is a ton of support for a startup like mine. However I am only 20 years old and still a little scared to put it all on the line. I also have the opportunity to travel to Australia for an exchange and I think it would be amazing. However the opportunity cost would be putting my startup on hold for the time being.