Origin : While I would love to do A, I cannot wait to do B.
"While~do A" is an adverbial clause(an adverbial clause is also an adverb).
I cannot wait to do B while I would love to do A. We removed the comma.
It looks more easy now.
But you should remind that "while clause" almost always(as I know) is closely related with main clause so you need to take care when you input something.
Some general rules for em dash
- Colon-like use : Simple equivalence (or near-equivalence) of colon and em dash
Three alkali metals are the usual substituents: sodium, potassium, and lithium.
Three alkali metals are the usual substituents—sodium, potassium, and lithium.
- Inversion of the function of a colon
These are the colors of the flag: red, white, and blue.
Red, white, and blue—these are the colors of the flag.
- Parenthesis-like use : Simple equivalence (or near-equivalence) of paired parenthetical marks
Three alkali metals (sodium, potassium, and lithium) are the usual substituents.
Three alkali metals—sodium, potassium, and lithium—are the usual substituents.
The food, which was delicious, reminded me of home.
The food—which was delicious—reminded me of home.
The food (which was delicious) reminded me of home.