The song shows male insecurity in a funny way. Ken is a himbo. He's insecure because he's hot but dumb. He wants Barbie's affection but he feels inadequate and Barbie is on her own journey.
The song is funny because he sings about being adequate and not really anything impressive. The tune of the song is an epic rock ballad, similar to the sounds of like "The boys are back in town", "We are the champions", "Eye of the tiger", etc. The expectation we have is that the lyrics of the song will be boisterous with claims of greatness, but Ken just wants to be normal.
This contrast is funny, but also Ken's desire to just be adequate instead of extraordinary evokes empathy from the audience.
♫ I'm just Ken and I'm enough and I'm great at doing stuff. ♫