The meal can easily be re heated in an oven or microwave but must be keep covered so the guest can see the rabbinic certifications seal is intact. In most major cities there are supermarkets, shops and caterers that provide kosher prepared foods and products. Many Jewish people practice some or all of these restrictions in various degrees. It would be best to inquire as to what if any restrictions they have. No pork, and shellfish.
Fish is acceptable as long as it has fins and scales.
This religion has various food restrictions according to there own dietary laws, which are Halaal. Muslim celebrate the birth of Mohammed at the end of February or early in March. During the holy month of Ramadan, Muslims are not allowed to eat from dawn to sunset. However young children, pregnant women and the sick are often exempted. As similar to other religions, it would be advisable to enquire as to what restrictions the guest has.