You have a very good question and many of my students do research papers on different organizations that try to help the homeless in different ways. You might want to rephrase the question to focus it a bit more:
What is the best solution to homelessness?
How can an individual best help solve the problem of homelessness?
Which method of solving the problem of homelessness is the most effective?
How can we eliminate homelessness?
Some of the possible solution ideas are:
Focus on substance abuse treatment.
Build more housing.
Give people vouchers for places to stay.
Expand work programs.
Give job training.
Provide affordable housing.
Give people assistance and training in handling finances.
Organize a program to help people get the social services available.
Provide better help and job training for Veterans.
Provide long-term spiritual and emotional counseling.
Create a mentorship program to help each individual homeless person.