Need some advice!

So two days ago I got a call from my son's school, he is only 6yrs old and it was the counselor and she said that my son has been telling her about the issues that he is having with his dad. And that his dad doesn't play with him, and his dad tells me that he's going to take him away from me, and his dad told him " F*** you man you need to spend the night with me" and I hate it when is dad tells him this it hurts me so much to see the look on his face when he hears that from his own dad and I'm like well no wonder he doesn't ever wants to go with his dad he disrespect him but his dad doesn't get it and so the school counselor was telling me that my son has a plan if his dad didn't want to bring him back home that he was going to wait until his dad was asleep and then he was going to sneak out of the house and get on the bus just to come home. Now hearing this from my only child got me scared and worried and what I want to do is Bann all visitation rights from his dad. Because to me no man should ever talk to his son that way and I just want to know what can I do legally to get him to have all rights taken away from him? I feel like he is verbally abusing his son! I have so much on my plate right now from being diagnosed with cancer to trying to be the best mom for my son!