Let's say you are describing the benefits of a healthy family relationship.
if every person had a healthy family relationship, this would yield a positive impact not only on every person, but also on communities as a whole.
Or
if every person had a healthy family relationship, this would yield a positive impact not only on every person, but also on a community as a whole.
Which is grammatical or appropriate?
if every person had a healthy family relationship, this would yield a positive impact not only on every person, but also on communities as a whole.
and
if every person had a healthy family relationship, this would yield a positive impact not only on every person, but also on a community as a whole.
are both grammatically correct, however
if every person had a healthy family relationship, this would yield a positive impact not only on every person, but also on the community as a whole.
where the community is the people of the earth.