I'm considering getting a flash drive & using it to manually back up my new phone(Pixel8).
I have 2 big questions.
1) Can I have multiple backups on a single flash drive or must I use another flash drive each time that I want to back up my phone?
2) Can I view the files on my Mac without any software or must I install some software in order to view the files?
1 You can backup as much data as you can on a single flash drive, but that's all dependent on two big variables -- how much data are you backing up and how much storage capacity does the flash drive have.
A hypothetical example being if you have 10 GBs of data on your Pixel to back up and you have a 500 GB flash drive than there's plenty of storage space for multiple backups. Conversely if you have 25 GBs of data to back up and a 50 GB flash drive, you only have enough space for a couple of full backups. And that also brings up an important aspect that has a lot relevance -- do you intend to do full backups of all your data each time or a more practical method of full backups of only new and altered files? The former wastes more time and wastes otherwise usable storage space, the latter is more efficient and the end result is still a full, restorable backup.
You're better off using a backup utility than manually copying over files. By doing a full backup of everything, each resulting backup is essentially the same as the previous backup but with newly added files and edited files. A backup utility makes an initial full back up of everything, than each succeeding, incremental backup only involves new and edited files. That first backup takes more time but each succeeding backup is much quicker. And does not waste storage space with duplicate data/files the way manual, full backups do.
2 That depends on what kind of files you have on your Pixel. File types like jpg, mp3, mkv, txt, etc. won't be a problem. A dbx file (database) will most likely be a problem, but that's not so much an operating system difference issue but the source app that created it and the application you're using to view it. There are dozens of variables to account for. please be specific as to what kinds of files are involved.