Parashas Tetzaveh · Passuk 29:38
Chabad.org — English translation + Rashi
Torah Temimah points to Menachos 29a (verified).
Sefaria — Exodus 29:38
Sefaria — Menachos 29a
E-Daf — Menachos 29a
English: Some Sages teach that the laws of shechitah were difficult for Moshe until Hashem showed them to him with a finger, as indicated by “and this is what you shall do upon the altar.”
On the daf / in context: See the cited source for the full section.
Derash on the verse.
The demonstrative “this” is read as indicating that Moshe was shown the practical details of shechitah.