Guadagnarsi il pane (la vita) col sudore della fronte is similar to "sing for one's supper." (Reference: Treccani.it)
Keep in mind, however, that it has some cultural history (detailed below) not to mention alliteration, that one can't easily duplicate. There is also something about it that is slightly archaic.
To sing for one's supper, meaning:
Work for one's pay or reward, as in Entertaining visiting scientists
is part of the job; you know I have to sing for my supper.
This metaphoric term alludes to wandering minstrels who performed in
taverns and were paid with a meal. First recorded in 1609, it gained
currency with the familiar nursery rhyme, “Little Tommy Tucker, sings
for his supper” (c. 1744).
Here is the text of the nursery rhyme, "Little Tommy Tucker, sings for his supper
"
The saying was further popularized with a musical number "Sing For Your Supper" from the "The Boys from Syracuse" in 1938.