While the first-fruits were being offered, it is stated in Deuteronomy 26:10 that after the declaration of the person offering, they would "prostrate themselves before Hashem."
Where would they prostrate themselves towards, and how?
Also, is this the only offering in which the person would prostrate themselves?
The Ralbag Biur HaMilos explains this bowing to mean that everyone who enters the Beis HaMikdash (Temple) bows down before G-d and this is next to the Kodesh Kodashim (Holy of Holies)
The Chizkuni adds:
והשתחוית “you will bow down” - as people do when taking leave of a superior such as a Rabbi.
As to how they would bow, the Malbim quotes Rambam that the bowing was with the hands and feet
