Rule change for draft. It's a long one with lots of movings parts.
The concept of a first round pick still exist -- each team still have one, and each team can trade its pick.
However, there's no order, and the pick should be understood as the right to offer a NHL contract to any player whose rights don't belong to an NHL team. The player obviously has to accept the deal for the pick to be used. 2nd round to 7th round go normally, a few days after the first "round" signees are announced.
Consequently, draft age would be pushed back a year, and every signee is eligible to play in the AHL. Arrangements can be made for loans (if a draft-eligible player is already under a pro contract and that player doesn't have an out clause, the player can still be signed, though a year is obviously burned in that scenario). Those first rounders have to be signed for 3 years (it can be 2-way deals, but it doesn't have to), and the max deal than can be signed is a fixed proportion of the cap, but for 2024, that maximum would be 4 millions (I didn't think about it that much, it can be different).
Concretely : For the 2024 team, any NHL team could've offered a 3 X 4M deal to Connor Bedard, provided that team has the caproom for it. It wouldn't have made any much sense to sign Matvei Michkov with a first rounder, but he could safely be drafted with a 2nd rounder.