Can someone recomanmand a shojo manga where the girl is very hardworking and has multiple ...

The Heirs? You probably have watched it though, it's very popular. I don't remember anything else.

Maybe Coffee Prince. It's the best gender bender k-drama, if that's your cup of tea

of course
http://www.mangago.me/read-manga/hana_yori_dango/
also http://www.mangago.me/read-manga/saesang_bring_it_on/
she only has 1 job but its kinda hard
http://www.mangago.me/read-manga/momoiro_heaven/
same, 1 job but father is a gamer...
http://www.mangago.me/read-manga/hapi_mari/
more mature
http://www.mangago.me/read-manga/diamond_life/

upsy daisy... k-drama...
but they made a k-drama about hana y d :)
maybe here are some suggestions?
https://youtu.be/N17G47xkOqo

Thank you

Thank you

Thank you

Thank you