Try this one and take also a look into the CONSOLE!
Which resulst and messages do you get there?
import wixData from'wix-data';
import wixLocation from'wix-location';
$w.onReady(()=>{
$w("#dataset1").onReady(()=>{
$w('#dropdown1').onChange((event)={console.log("DropDown-changed")
console.log(event.target.selectedIndex)
$w("#dataset1").setCurrentItemIndex(event.target.selectedIndex)
})
})
$w("#button1").onClick(()=>{console.log("Button-clicked")
wixLocation.to($w("#dataset1").getCurrentItem().url)
})
})
Do your button-actions work ?