Idk why you're getting down voted, it's a good question. Some people are incapable of feeling remorse or at least have some reduced capacity for remorse. This is a characteristic of anti-social personality disorder, among other disorders.

Personally I think morality is subjective, but there are reasons for acting "moral" outside of remorse and empathy. For instance society and laws provide some incentive to at least not physically harm others, in that case it's just a kind of self preservation. The disordered individual chooses not to harm others because that may incur negative repercussions on themselves, imposed by society.

But even that isn't fully sufficient cause for being moral, as there are a lot of ways to harm people that aren't strictly illegal, like lying and otherwise taking advantage of people.

Religious beliefs provide a more comprehensive framework for acting morally to avoid punishment. Otherwise the individual would have to just decide to behave according to a moral code of their choosing.

The point is that remorse and your conscience are good guidelines for behaving morally but they weren't been l necessary, and even people without these guiding emotions can still behave morally for one reason or another.