Is it bad to accept a job then decline?
It's better to decline the offer than to quit shortly after taking the job. It's more expensive for the company to onboard you, then start over with a new candidate search. You also may have to explain why you quit a job you just started during subsequent interviews.
Can you withdraw from a job offer after accepting?
Declining a job offer after accepting is not ideal, but it can be done. In fact, turning down a job offer after accepting is easier than accepting an offer you've previously declined. That's why you need to be certain that you can't negotiate a better deal and won't change your mind before rejecting a job offer.
How do I reject a job offer after accepting it?
Related Question what if i accept a job offer and then decline
Is it bad to accept a job offer and keep looking?
In general, it is a terrible idea to accept an offer and continue to interview. While most work agreements are employment-at-will so you can quit at any time, you don't want to be someone who quits shortly after accepting an offer.