If I were to express this sentiment I would do so as follows "Sometimes a simple word of encouragement or a smile means a lot to someone, I wish more people would do something nice for people who need help." By stating "I hope more people can do something nice to whoever needs help." It implies that you want people to do something they cannot currently do "can do" rather than "would do" which would mean they have the ability but lack the inclination to. Good effort :-)

Yes, just say "for whomever" instead of "to whoever" and you're good to go! [emoji]

Yes, for real