Welcome to the forum Dario
Angular edges are a modern thing, as everyone seems obsessed with big looking bats (see the trend for heavily concaved bats with 45-50mm at the moment to get my point).
When you get your new bat, round the edges with your bat mallet.
If you look on Youtube, Paul from
@ItsJustCricket has done an excellent video on the knocking in process that shows how to do it properly.
As for using it in a match, I'd personally get it fully knocked in then net against old balls for a few sessions. Once you're confident it's played in and no seam marks are appearing from use against the old ball it's ready to be taken into the middle. If you open or face a new ball regularly I'd play it in for a bit longer than if you come in down the order when the ball isn't quite so hard.