NET Bible
"The Work of the Levites Then the LORD spoke to Moses:"
— Numbers 8:23, NET Bible
So Moses and Aaron and the entire community of the Israelites did this with the Levites. According to all that the LORD commanded Moses concerning the Levites, this is what the Israelites did with them.
The Levites purified themselves and washed their clothing; then Aaron presented them like a wave offering before the LORD, and Aaron made atonement for them to purify them.
After this, the Levites went in to do their work in the tent of meeting before Aaron and before his sons. As the LORD had commanded Moses concerning the Levites, so they did.
The Work of the Levites Then the LORD spoke to Moses:
“This is what pertains to the Levites: At the age of twenty-five years and upward one may begin to join the company in the work of the tent of meeting,
and at the age of fifty years they must retire from performing the work and may no longer work.
They may assist their colleagues in the tent of meeting, to attend to needs, but they must do no work. This is the way you must establish the Levites regarding their duties.”