Nomodeset isn't a solution, just a temporary workaround.

And your very own link clearly mentions 20.04. Why not use that? It seems that you misread and/or are misinterpreting a lot here.
The minimal requirements are about a minimal kernel version, not a specific kernel version. It makes no sense to insist in using 18.04.4 when there's a newer point release. And, again, 20.04 CAN be used. The 18.04.4 that you install now will be upgrade to 18.04.5 in a couple of minutes just by installing the proposed updates therefore installing specifically 18.04.4 is a complete nonsense.

Now, circling back to the beginning, "nomodeset" (+ Secure Boot) prevents loading proprietary drivers for graphics among other things that can very well include the hardware you want to run. So, it's another nonsense that you think is a solution but it really isn't. The solution should be the opposite, i.e., disable Secure Boot, NOT use "nomodeset", install the latest LTS, 20.04.