Death is a difficult thing to cope with regardless of one's religion or background. Knowing how to act appropriately with a Muslim family member or friend at the time of a loved one's death is simply a matter of self-education.
Because of the Muslim focus on simplicity, gifts to the family after the death of a loved one are not appropriate, according to A to Z Guide to Manners and Etiquette. If you want to show your respect, attending the burial or visiting the family during the period of mourning are appropriate responses.
Muslims likewise do not send flowers to a funeral, according to The Light Beyond.
Meals can be provided to mourning families, particularly in the three days following the burial. Be very careful that the food you provide follows Islam's dietary restrictions. It is wise to coordinate with other friends and family who may be bringing food as well.