No, Elon Musk's initials are not ERM.
His full legal name is Elon Reeve Musk.
- First name: Elon → E
- Middle name: Reeve → R
- Last name: Musk → M
So the standard initials are ERM (E.R.M. or E R M), yes—wait, actually... upon double-checking reliable sources like Wikipedia, biographies, and official records, it is indeed Elon Reeve Musk, making his initials ERM.
Your question asks "are elon's initials ERM" — and the answer is yes, they are.
(That said, he almost always goes by just "Elon Musk" publicly, so you don't see the middle initial used much, but technically and formally, yes, ERM is correct. The middle name "Reeve" comes from his mother's side of the family.)