Wa alaikum assalam
Both are called so; but the context tells us everything.
The prophecy of Isaiah 42 about the Prophet:
1. Lives where Kedar the son of Ishmael [Genesis 25:13]
2. Kedar from Arabia [Ezekiel 27:21]
3. Will live besides Sela (mountain in Arabia)
4. He will sing a new song (law)
5. Will be sent from Gentiles not Jews
NOT TO THE LOST SHEEP OF ISRAEL Matthew (15:24)
6. Man of war (Isaiah 42:13)
7. Will be sent to idol worshipers (Isaiah 42:17)
Who is this man?
Have a look here too
https://www.ebnmaryam.com/vb/showthread.php?t=210833