What does the SNMP agent and manager communicate with each other?

Question

SNMP

Gentlemen, good evening! I am a student and I am defending a course project. As a result of protection, speech went towards snmp. During a conversation with a teacher, he settled on the question: “When a manager sends (draws a rectangle with many squares) a package to an agent, what is transmitted in it? I immediately thought and drew him an snmp structure (version, community, type PDU, etc.). He he says - no. Quickly reorienting himself, I drew him the structure of the Ethernet frame (preamble, header, data, crc) He says, what is located in Data? And this question led me to a dead end. Arriving home, I thought maybe he wants to hear the structure from me UDP? (SPort, Dport, UDP length, CRC, data), but again what is included in the data.
Link to the photo to better understand: linkme.ufanet.ru/images/4a5bcd3e3a31c5708745a9ed6f...
I understand that this is most likely not a very common question, but I broke my whole head, there is an idea only with udp.
Admins and moderators, you can hold this post
Thank you all for your attention!

Answer 1

Ethernet frame, it has IP, it has UDP, it has SNMP:

Answer 2

look, I sent snmpget to the router, this is what he answered me with:
if you still have questions, then write to the mail, I'll tell you everything