I wouldn't get anemones. Especially for your first tank. IMO
with a small tank you don't have enough margin of error to keep a sensitive invert like that.
If you buy cured LR
I still wouldn't trust putting it in your tank directly. To cure live rock you just need some aquarium heaters, a lot of buckets and power heads, salt mix and RO
water and patience.
Oh and what do you mean by live sand? That bagged mud you see at the pet store is a rip off, it's been sitting there for months already. If I were to take one of my filter pads and stuff it into a plastic bag filled with water and leave it for a few months, it would oh so certainly not be "live" any more.
The beneficial bacteria in "live sand" will come with any live rock and from free floating spores in the atmosphere. They will also colonize anything, regardless of what it is; your tank glass, your filter, your rocks, sand, crushed coral substrate, aragonite, will all develop bacteria on it.