NOPE
Can I rob my grandmother's cafe?
No, unless you want a personal invitation to court and maybe prison.
Robbing your grandmother's cafe is a spectacularly bad idea, legally and morally. Besides facing serious criminal charges, expect family drama that lasts longer than your sentence would. Just don't do it — steal something less complicated, like a snack from the fridge.
Attempting robbery is a serious crime with legal consequences. If you are struggling financially, seek legal assistance or social support agencies instead.