There is no ST app for a PC or Mac, but you can access the my.smartthings.com website which gives you some minimum control over your devices. There are also the ST CLI which is a command line tool that let you get information about your environment as well as issue commands to devices. For just looking at information about your environment (and some minimum control), there is also the community developed API Browser+.
If it is SmartThings Find you are interested in then your best option is probably the https://smartthingsfind.samsung.com website. That allows you to track your own Samsung phones and SmartTags but not those of other SmartThings Location members as in the SmartThings mobile apps. Not sure about the other stuff like Buds.
There is a SmartThings app for Windows but it is pretty basic and most importantly it only supports SmartThings Find on certain Samsung Galaxy Books.