I'm sorta new here and am still learning the game. Is there a way to expand your hols so you can bury more things? I keep finding more relics that I can bury and they keep getting stolen. I have looked around and have not found a way to expand my horizons. Is there a way to do this?

you need apples which you can buy using real money or from other players then go to Realm>Barter>Apples>item hole expansion or food hole expansion if you want to bury food

Most relics you can sell at Realm > Montak's. They have practically no use and are just pawned off with a badger.