Numbers 6:14

¹⁴ and he shall offer his offering to Yahweh, one male lamb a year old without blemish for a burnt offering, and one ewe lamb a year old without blemish for a sin offering, and one ram without blemish for peace offerings,

Shave the head

'To shave the head' was strictly prohibited for the high-priests and his sons because of the holy representation of hair and of the Nazarite.