I'll give you a general answer.
Muslims believe that God/Allah is not like his creation and therefore doesn't need anything whilst the whole of creation needs God.
Sometimes if people seem to get away with things on this earth that because the punishment is going to given to them on the day of judgement. This is the day of justice and this is day that anyone who did wrong will be paid back his evil and given the good of his works also.
Even if people don't believe that there will be a day of reckoning that even the smallest good and the smallest evil will be repaid to the doer.
There is no doubt in this