Location Selector with session storage for loops

Hey guys, pretty advanced question, maybe wrong place to ask.

I have a “find your location” page.

On there, i loop through ALL my Locations in a query. Information regarding the location then gets output. Now, i dont want ALL my locations to be displayed.

Thats why i will have a dropdown with “choose your location” that loops through all locations again and then selects one. That kind of location selector i already have on the site, so a value gets stored in a session storage already.

The desireble outcome is this: The Loop is only displayed IF a location is selected. and if a location is selected, obviously, only this location is then loaded in. How would i best set that up?