John Gill Commentary Leviticus 8:21

"And he washed the inwards and the legs with water; and Moses burnt the whole ram upon the altar: it was a burnt-offering for a sweet savor: it was an offering made by fire unto Jehovah; as Jehovah commanded Moses." — Leviticus 8:21 (ASV)

And he washed the inwards and the legs in water
The one being taken out, the other cut off:

and Moses burnt the whole ram upon the altar: it [was] a burnt
sacrifice for a sweet savour, [and] an offering made by fire unto
the Lord; as the Lord commanded Moses ;
see (Exodus 29:18) .