How should we act to be of benefit to others in this world? If everyone behaves in a way that benefits each other, rather than seeking personal happiness alone, and instead spreads happiness to everyone, that is the ideal.
Start with parents by ensuring that all children achieve a higher level of education and secure prestigious jobs. Provide for parents to live comfortably, akin to deities. This is considered benefiting the children and descendants first. Relatives should also act similarly, helping each other to be self-reliant and not dependent on others. Benefit your neighbors by sharing knowledge and providing happiness to fellow humans. Whatever prosperity or success they achieve, contribute to it in that manner. This is what it means to be beneficial to one another..
Source: “The Legacy of Dhamma,” Volume 1, Pages 217-218 (Khandha 6: Socially Useful Acts, September 20, 1953)