have your cake and eat it (too)
US /hæv jʊər keɪk ænd iːt ɪt tuː/
UK /hæv jʊər keɪk ænd iːt ɪt tuː/

1.
tenerlo todo, querer lo imposible
to want or try to do two things that are impossible to do at the same time
:
•
You can't have your cake and eat it too; you need to choose between your career and your hobby.
No puedes tenerlo todo; necesitas elegir entre tu carrera y tu pasatiempo.
•
She wants to work full-time and also travel the world, but she can't have her cake and eat it too.
Ella quiere trabajar a tiempo completo y también viajar por el mundo, pero no puede tenerlo todo.