How many times dividend are declare in mutual funds ,ELSS , or stocks?

I am a new investor , I wish to ask that how many times dividend are declare annually ( in one year ) in any of the mutual funds , ELSS ,or stocks , also I wish to ask if any of the mutual funds are facing loss so also it will declare the dividend or not , can any one say in very simple example how NAV is calculated , please help me .
please some body give me some more details .