Caching issue - Any way to force a hard refresh (or fake it with random numbers)?

Is there any way to force a hard refresh, or barring that, to add a random number to a menu url?

My server has caching that I can’t over-ride (as do many browsers) so my blog index page doesn’t always show the latest posts.

Everyone who tests it for me sees a slightly delayed version unless they hard refresh.

If I add a random text string like ?2318098 to the url it forces a hard refresh and show the updated post archive index.

I was thinking if I could make the home page link be www. websitehomepage.com/?[randomnumbershere] then it would be a hack to override the caching issues but maybe there is a simple way to force a hard refresh (sometimes?)

Any ideas welcome!