Sizing the partitions is a step you (can) take when formatting the drive… And from what I can tell the Envy has an M2 nvme in it, and it just seems crazy to me to basically just ignore that to boot off of an SD card/USB drive…
How sure are you that you want to be using Linux? Lol
It never fails; Whenever I see someone apologizing for their ‘poor English’ it’s almost always essentially flawless (or, at least, better than the majority of native speakers anyway lol)