If all the acorns around you have got your feeling a little squirrely, here’s the short, short version of what you can do:
If you have Valley Oak or similar acorns (they are cream colored “white” as opposed to yellow), crack them easily with a nutcracker or a rock against a hard surface. Grind them up as fine as you can, and then leach them in a cheesecloth or similar straining device. Leach by tying to a hose spigot or a faucet and let drip overnight or until no longer too bitter/astringent tasting. Use that as wet flour/meal or dehydrate to make dry flour.
To store: best way is to process them all now to make flour. You’ll thank yourself for this later, but I never seem to get around to it, either. Typically, the freezer is your friend here. Otherwise, in a dry area in shallow layers, as too many acorns packed together will rot fast.
Sprouted ones (little roots just peaking out of the shell) are good to eat.