Buddhist centers often have options for those who have trouble paying, and mental health providers sometimes will offer a sliding scale. Insurance might cover it if it’s through a health provider. But they are fairly intensive 8 week programs, and instructors have to go through a standard training and certification program, so it’s quite an investment to run them, and I don’t know that you’d be able to find one completely for free, though there might be a recorded or self paced version you can access.