John Gill Commentary Leviticus 9:13

"And they delivered the burnt-offering unto him, piece by piece, and the head: and he burnt them upon the altar." — Leviticus 9:13 (ASV)

And they presented the burnt offering to him
After it was cut in pieces, as the ram of the burnt offering was by Moses, (Leviticus 8:20) and so it was done to this, as appears by what follows: with the pieces thereof, and the head, and he burnt them upon the
al tar ;
the Septuagint version is, "he put them on the altar".