My x said he will take my kids away

Hes saying he wants 50/50 so he doesnt have to pay child support. Ladies i am scared. He hasnt seen them in 2 months because weve been doing nothing but fighting. He doesnt want to come and see them at my parents because he doesnt want to be "babysitted" but he is not responsible to watch our 2 year old and 10 month old. Hes always high and smokes mutiple times a day and has never watched them longer then 3 hours and those times he did nothin to make sure they were taken care of. He refuses to work and has been on and off job. He did uber but would stop for weeks then do it for a day out the month and stop. He wanted to sell drugs which i refused to let it happen and a month later we broke up. I still had passwords to his fb and seen he started selling but he caught onto it and changed his password. I wasnt able to save that information, i kepttrying to give him options to see the kids, i was the one always going to him and trying to work a plan. He then said he'll give me money but i told him he will be put on child support. I dont want his drug dealing money i want him to find a job and do right for my kids. Ofcourse he got mad so we didnt agree to anything. Now i found out he is trying to look for a job at this one place i begged him to apply for because they had paid him good a few years ago but he got fired i dont know if hes scared that iwill take him to court and is trying to look good and try to demand 50/50 and do whatever he can to just not pay child support n say he has a job now and whatnot. We lived at one of his moms houses and she will lie for him and say he pays rent when he never would, and doesnt. His cousin and her man and 3 kids live there as well but iknow he will tell them he has a place and rooms for them and its killing me. He will pay for whatever pills to detox so if they drug test him it will look like i lied. This man has never been there for his kids. He would constantly leave to go get high. He would leave me for DAYS or nights with no car no help to get high. Anytime we argue he would use whstever excuse to leave. I would run out of formula or dispers and he would not come back. My stupid old phone had every proof i had to say what im saying is true but it cracked and now i have nothing besides me going to his mom and explaining everything hes done. Even when my son was at the hospital he wasnt present. Is there anything i can do? I ddi everything on my own i will never stop him from seeing his kids but this isnt fair. My kids dont even speak yet and all this is overwhelming me. Any advice? I live in illinois