Hire competent supervisors. If you can't handle your own and leave your mess at home, maybe customer service isn't for you.
To be ontime and not be late
Talk to employees if they have any problem regarding this job, ask if they need extra hours or they need more time to give their family.
Complete Management Change
Work on treating employees with respect, cleanliness, new food preparation habits
Have someone check up on the higher ups like the shift manager and not just the people working their part-time.
There really is no reason on why I should tell you to leave. It is your choice.
Hire a new manager or give less workload so people will not stress out
Increase the salary to be more competitive.