The most recent Nintendo Direct went into great detail on the new Switch 2, including when fans will be able to get their hands on the console. According to Nintendo's press release, pre-orders for the Switch 2 open up on April 9 in North America,

Amazon is now taking Nintendo Switch 2 pre-order invite registrations. You'll need to hit the "Request Invite" button on the page to put your name in the hat, but doing so doesn't guarantee a pre-order or even a slot in the first wave. It is a necessary step to getting into the mix at all, though.