Mike,On the Dual Boot Desktop I just built I boot to the Linux SSD in Bios, first thing that pops up is Grub..
1. Boot to Linux Mint
2. Boot To Linux Mint Command Prompt
3. Boot to Windows OS
4. Boot to Bios
Only issue was an AMD CPU Upgrade (Yeah Like after 2 months old) And Bios reverted back to the NVME boot. Just had to change it back to Linux SSD. Because Linux sees Windows.
On HP laptops I have found it does not like dual booting without the On hold Del option. Start with Windows and it will steal your Linux boot options. Maybe not right away but some update will eventually do so.
yeah, i have another laptop and it does this as well, no issues from that standpoint it just boots right into grub and I can select my OS i want to boot to. I don't know, until i ran into this i didn't even know this issue was a thing. Oh well.