Very simple, here is the command to convert man page of ls command to text file:
man ls | col -b > ls.txt
Then use lpr print command to print ls.txt file i.e. it sends a print job to the default system queue/printer connected to Linux/UNIX:
cat ls.txt | lpr
OR
lpr ls.txt
You can also try:
man ls | col -b | lpr
You can also print GNU Linux info pages:
info ls | col -b| lpr
Please note col command filter reverse line feeds from input i.e it removes \r \n like character.