You can read a summary here.
Like the 1994 ban, it would cap magazine size at ten rounds, ban a number of weapons by name, and also ban guns with certain cosmetic features. However, it would define as an “assault weapon” any gun with one of these features rather than two, and it would remove flash suppressors and bayonet mounts from the list. The other features in the 1994 ban for rifles were folding stocks, pistol grips, and grenade launchers. For pistols they included magazines that attach anywhere but the grip, threaded barrels, and barrel shrouds.
Also like the previous ban, the proposal would grandfather in all guns that are currently owned legally — but this time around, these guns’ owners would need to register them with the federal government.
I don’t see this going anywhere — and there’s no reason to think it will do anything to reduce gun violence even if it becomes law.