Button have different URL based on condition

I’m beginner in Code. I want to create button that have different url based on condition that user choose.

So for example the button called “Book Now”
I have to package using span: Standard and Premium

My plan is, if user choose “standard” the button will be have “html://blablabla.com/standard
and if user choose “premium” the url will be “html://blablabla.com/premium

I was wondering how it can be possible in html and javascript?