Question

What is a helping and main Verb.

Answer 1

Main verbs are verbs that represent the chief action of the sentence.Helping verbs are verbs that support the main verb.Main verb has real meaning and tells more about action while helping verb has no (or little) meaning if it is alone but it adds time information about action if used with main verb to specify the tense or time of the main verb.
The examples below will help in better understanding.    
She is eating an apple. (“eat” is main verb while “is” is helping verb) 
She was eating an apple. (“eat” is main verb while “was” is helping verb)

Answer 2

philanthropists will be donated in this sentence philanthropists is subject, will be is helping verb and donated is main verb because it is a activity