The future hasn't happened yet, and this will always be true.
So how does this affect the characters in your story?
Here's a couple of answers to get you started:
1) Same as in real life.
2) Way different to real life.
If this sounds unhelpful, remember what Walt Whitman said in Song of Myself:
"Pesky racoon damn near bit my toe off
then some dumb bee stung my naked ass."
That, my friends, is the epitome of unhelpful — which is why Whitman replaced the whole raging at the denizens of nature section with all that stuff about “containing multitudes”. Smart guy, in spite of the ludicrous beard, it seems.
The truth is that the future matters to your characters like it matters to real people. They will mistakenly believe they can PREDICT it. Worse still, they may think they OWN IT. Truth is, everyone is the world's greatest clairvoyant in their own head (especially those who believe they have no control over events).
In a world of lions and angels, we've evolved to be this way. We've evolved to GENERATE COPIOUS AMOUNTS OF FICTION. Especially fiction about the future!
And this is where conflict comes in.
When your characters fight, almost always what's at issue is THE FUTURE. Mine versus Yours, no inbetweeny compromise. In the real world of your characters’ fictional lives there are duels involving swords and laser zappers, but behind the dotted i’s of their prosey existence, two nebulous bundles of motivation battle for supremacy with the fury of selfish genes. (It's true that speculation about the future doesn't always involve conflict, but all that stuff is for recipe books and compendiums of LOLcats.)
What's important here for writers is that the generators of this necessary-for-survival FANCY are themselves creatures of pure fiction. In real life we get to dip only one ladle of speculation into one home turf muse pool, but when we’re writing, we have the luxury of manipulating an imagined imaginer and an imagined imagination. In speculative terms, it’s a dual wield Ladle of Fancy scenario, and WAY DIFFERENT TO REAL LIFE.
Your characters’ clairvoyant savantery is potentially boundless, and you can tweak the parameters of their conflict (within a potentially boundless conflicting world/milieu) WAY MORE than you could in real life — not that you would ever want to become a confirmed parameter tweaker in the supermarket or at work, of course: you’d be arrested on the spot.
In fiction — the battle for the future — everything can (and must) be BIGGED ON UP till any conflicts thus generated whoosh past the Alien versus Predator scale and on into 'Putin takes on the Cosmos wearing only a leotard' territory. If you get it wrong, you can always tone it down, but in the first instance (the speculative instance) it’s necessary to crank all the dials way past the Spinal Tap threshold, the humble 11.
I'll say it again: the future hasn't happened yet, and this will always be true.
Real people argue over it, clashing against one another with their real imaginations, their ideas of “how things could be”.
Your characters live and breathe in truly morphable worlds, and you may tinker with their inner workings like Gandalf combing his hair and beard a follicle at a time for Maximum Fantasy Wizard Effect.
Gift your characters a perfect future — then poise it on the tip of a dagger gripped by a demon. And write it all down...