How do I tell him what I really feel without sounding rude?

So my boyfriend and I have been dating for several months. He's 30, I'm 29. He's been not doing well with keeping a job. He also seems quite immature for his age. I can deal with some quirks here and there, but I'm starting to really not tolerate how he doesn't have his shit together right now. I'm a responsible adult, with a stable career , full time job. This man doesn't have anything saved up for the future, likes to play his video games a lot, and still hangs out with his loser friends who are just like him. Side note , he's previously divorced due to a bad marriage. He just quit his job again because he's supposedly moving to another area soon, and trying to fix his car so he can get it back in the road again. How do I carefully tell him that if he doesn't get his shit together right now, that I will dump his ass. I have a very low tolerance with dusty, lazy ass men at this point in my life.

Updates
1 y
I forgot to mention. He still lives with his parents, in a filthy messy home, he still asks his mommy if he could borrow money for gas.
How do I tell him what I really feel without sounding rude?
Post Opinion