(though I may have to keep typing the parameter every time, and is it supposed to take like 10 min?).
Sorry I lost track of the discussion, but was this about editing the grub boot parameters?
If you do that in the grub boot menu with 'e', then yes that is only a temporary change.
If you want to make it permanent, Cavalry's link https://forums.linuxmint.com/viewtopic.php?t=220493
mentioned that later in the instructions. (Those instructions seem a bit outdated as the example uses the "gksu" command that is apparently now a deprecated command, at least my Linux Mint 19.3 doesn't seem to have that command anymore, and googling for it suggests it was removed some time ago.)
So you need to edit the text file /etc/default/grub (as a root or sudo user), specifically the line GRUB_CMDLINE_LINUX_DEFAULT= and after saving the file, run "sudo update-grub". I lost track what exactly you are supposed to put there (adam mentioned something and dtgreene too), hopefully you know what is supposed to be there. :)
So something like this (using the text editor "nano" below as it is more beginner-friendly than e.g. vi or vim which I normally use):
sudo nano /etc/default/grub
Make your changes and save the file, and exit nano.
General comment when you said people don't tell you exactly what to do and what something like grub means etc. Since we can't be sure how much you have learned by yourself (e.g. are you familiar how to edit text files in the bash shell like using nano or vi, do you know why you need to use "sudo" in front of commands etc.), just remember that google can be your friend.
For instance, what I said about "gksu" above, I just learned some minutes ago by googling. I wasn't even sure what "gksu" is and wondered why it was used in the linked example, so I googled for "linux gksu" and learned (or was reminded, if I've just forgotten) what it is used for, and that it is deprecated now.
So for instance if the question popped into your mind "what the heck is 'grub' that those guys mention?", just google for it. Since you have just entered a new OS that does most things differently than what you are used to, it is understandable to be ??? all the time.
And you don't have to remember all of it. Heck whenever I need to add or expand hard drive space (LVM) to client Linux servers, I pretty much always look at the instructions I've written to myself and copy&paste the exact commands from there. I haven't even tried to memorize all the "pvcreate this, lvextend that, resize2fs those" steps, just so that I don't make any big mistakes.
Also while I said google is your friend, it can be your enemy too. Lots of information there, just like here in GOG forums, may be either irrelevant to your case, or just plain wrong. Like last week I was trouble-shooting for a client why they suddenly couldn't use the "curl" command to upload files to an external server (which had updated their SSL certificate), there were oodles of possible explanations online what could cause the error they got, starting from some firewall intercepting the connection attempts.
However, in their case the problem turned out to be that their "curl" was a very old version. Simply just updating it fixed it for them; that was my first suggestion they should try. So they didn't have to try to check all their firewalls or the firewalls on the receiving end etc. :)
Also things change so some instructions online may be outdated, like the gksu example, or how I just recently learned that the "xfs_growfs" command in RHEL/CentOS/Oracle Linux 7.7 has apparently changed that I had to change my own instructions how to use it.