Cooked beets, instant pot option... try high pressure 15 to 20 minutes maybe, with steaming setup. No need to clean or peel till after they're cooked.
Cooked beets, roasted option... wrap each beet loosely in tin foil, roast at 375 F for 30 to 60 minutes? They're done once a fork or skewer slides easily into the centre of the beet. Immediately immerse in ice bath for easy skin removal.
After the beets are cooked, place them in a sink full of cold water. Have several large bowls ready for the peeled and cubed beets. Once they're cool enough to touch, use a paring knife to peel the skins off the beets and cube them to desired size.
Pickle the beets. Could get into safe canning procedures... or for now, might just make sure the pickling brine i'm using is acidic enough... is it accurate to call it a brine since it's acidic? I dunno...
Notes
Haven't tried yet... not really sure how I'm gonna cook em.
Note that raw beets are edible.
Orange slices, mustard seed, and orange juice might be nice additions?
A note on storage: since these aren't not canned in sanitized containers, they must be stored in the refrigerator. Refrigerator pickles for up to 2 months, but if any smell or flavour seems off, best to discard things and start over.