Have (one's) cake and eat it (too) British verb phrase UK informal common cliché
This phrase is often used with "can't".
To have or do two things that are typically incompatible or impossible to have or do at the same time.
When Jane is working at home, Jane can take care of her family and still earn money. She wants to have her cake and eat it too.
You can't have your cake and eat it. If you want to be paid high salary, you can't expect to work less.
You can't have your cake and eat it. My girlfriend and I can stay in a big house in high rental fees or we can stay in a small flat and the price is cheaper.
There can be good aspects that exist in a bad situation.
To lose the skill or advantage one used to have in the past
To gain an advantage over someone by doing something before them
To be in a better position than your opponent; to be in an aggressive or offensive condition or position
The verb "have" should be conjugated according to its tense.