In this context:
trying to become a staple amongst the community
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Something that has become both common and expected in the same sense that bread and milk are staple foods:
It's not a very good word choice. "Staple" is most commonly associated with basic foodstuffs. Flour, oil, and eggs are all "staples".
The meaning of the word has stretched somewhat, so anything that is considered to be necessary, central, or key can be described as a staple, but the food connotation usually restricts the usage.
This is metaphorical.
Being a "staple amongst the community" is a valuable attribute. This person is a pillar in the community. Some would also refer to the person as a rock. I just call them leaders, haha.
The word "amongst" is heard in British, Canadian, or Australian English. It is rarely heard in American English.
A "staple in your life" is a person, place, or thing holding your life together. Usually this is used when referring to person who is or has been a powerful influence in your life. My mother is a staple in my life. I can always count on her being there for me and holding things together.