Can anybody help with this ?

My son is 7 turning 8 in sept , his father has visitation but doesn’t help out with anything . He feels like I need to cal him for him to speak with his son and that’s a no no . He thinks he can text me harassing messages about me and my husband or about how he’ll be picking him up when he pleases . Doesn’t wanna help out financially and lives with his uncle with a whole girlfriend and child . He doesn’t have a job or high school education and think he’s supposed to be demanding somthing all the time . I want to speak to my sone about how his father isn’t a fit parent and idk where to start . My husband tells him all the time you don’t need that man I’m your dad , you don’t need a bad person in your life & he’s due to go down to N.C. for summer break . I will not let my son go down till school is finished because I have text where he said he doesn’t care about my son schooling or doing summer work . He tries to call and bribe my son with things we both know he isn’t going to buy . There’s been raidings and even had to get custody back because he was on Facebook live smoking weed in front of my son with 4 other people while my son was in the back . I’m not against weed but there’s limits and things you just don’t do & I definitely don’t want my son there this summer or ever again . He says he doesn’t get to go swimming and things during the summer and he’s just in the house with his cousins w no supervision. I’m so lost because my son is so precious to me