Opsec mandates to buy throwaway devices for such purposes.
The easiest way to travel state borders is to buy something like an old Dell Latitude (core2duo generation) with libreboot and a LUKS encrypted Linux on it.
Don't take your phone with you, especially if it's necessary for 2FA or can be (ab-)used for recovery of accounts.
Use a phone that's easily reflashable in case it gets compromised. Fairphone 3/3+ or Pinephone come to mind, depending on whether or not you want to deal with mobile Linux. Otherwise Xiamo Redmi Note 8/8T or devices with a MediaTek CPU. MediaTek ARM CPU has developer tools which have been leaked, and is a rootkit that can uninstall/reflash other rootkits :P
Note that there are already some rootkits in the ARM space so you also need to make sure the ARM blob hasn't changed, which is why I would not recommend a device that hasn't been integrated with the upstream kernel or hasn't got their blobs available.
Never use broadcom based wireless Hardware, because of broadpwn and bluepwn. Change the laptop's wifi card to an Atheros one.