I'm in way over my head but trying to swim (learn)!
I'm setting up a multi-purpose server. Part of my reason for doing so is to learn more about Linux. I'm an old hat at Windows but have lost my patience with MS. I'm a little past the noob stage- not much- and know just enough about linux to be dangerous! I'm using Mint 20.1 which I realize is not the best choice for a server but I'm already somewhat familiar with it. One thing I eventually want to do with it is a router/firewall/nat. So I picked up a cheap used HP NC364T Quad port enterprise network card on eBay which came highly recommended for this. The card has two Intel 82571EB (e1000e) processors and is supposed to show up as 2 dual port ethernet adapters. And it kinda does, but not completely.
Running lspci shows 4 adapters but when I go to network settings I only see 2, ens4f0 and ens4f1. And if I plug my cable into the first 2 ports I get a connection. Plug into the other 2 ports and I do not. HP has a driver package available for SuSE / Red Hat as an .rpm file. I have read that you can convert rpm to deb using alien but that seemed a bit dodgy to me, particularly for a driver and was nervous to try it without some confirmation. Also found a brief article saying I could extract the tar.gz and recompile it for Debian but the article did not go into any details, much less a step-by-step guide to do it. The readme file for the driver DOES include step-by-step instructions to compile it and they seem simple enough for me to follow. But the readme file also included the statement which again is over my head but sounds like it might not work. And I also suspect I may be overthinking this, and maybe all I need is a terminal command or two to enable the other half / other 2 ports, being as it apparently recognizes it is there.

What approach should I take to get the other 2 ports working?

Update: So I got the brilliant idea that maybe I should check the logs... and I found this:
So that leads me to believe that it is trying to assign the same names to the second pair of interfaces as to the first pair.
Googling this led me to several articles regarding naming interfaces by editing /etc/udev/rules.d/70-persistent-net.rules. The file didn't exist, so I created it as described in the articles and restarted. Alas, that did not fix or change anything and the same errors were logged again.
One of the articles also mentioned /dev/null /lib/udev/rules.d/80-net-setup-link.rules which is supposed to control 'Predictable Network Interface Names' (Telling udev how to name the interfaces?) but that file does not exist.
So knowing that everything in linux is treated as a file, I suspect I may need to:
Edit/fix/create a Predictable Network Interface Names rules file, or
Edit/fix a config file for udev (which? where?), or
Rename some files or links? Looking in /sys/class/net I found 5 folders: ens4f0, ens4f1, eth1, eth2, and lo (no eth0!) but cannot rename them, maybe need to stop service?
A bunch more googling has so far failed to lead me to a solution. But it does make me confident that I can fix this with a few commands in terminal and not have to fiddle with converting or recompiling drivers.

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