I was just release from prison and need help to buy clothes for myself and son

The only grants for felons aren't grants, they are education loans.
Every city and town in the nation has organizations that collect good used clothing and give it out for free - churches, shelters, women's groups, food pantries, and some once a year winter coat drives.
If you can't find any by asking neighbors, tell us where you live.

Call the reference desk at a public library near you. They will have a list of organizations (plus locations, contact names, phone numbers) that help people in need.

There are no grants for this, you can check out the Salvation Army, Good Will or a religious group of your choice. Many non profits help with needs.