Questions about updating servers

Hi!
We bought several new servers: Dell PowerEdge 760 and Dell PowerEdge 670.

There are no upgrade issues for the Dell PowerEdge 760 server. Through the "Lifecycle Controller" I have installed "MS Windows Server 2025". Then I downloaded the "Dell Server Update Utility, Windows 64-bit format" and then installed all the drivers and BIOS updates in the "MS Windows" OS. There were also firmware versions that wrote an error and did not allow installation inside the OS, so I booted into the "Lifecycle Controller" and opened this image there "Dell Server Update Utility, Windows 64-bit format.iso " and through the Lifecycle Controller, the rest of the updates were installed without problems. That is, everything is fine with Windows OS. It's simple.

And now the question about the Dell PowerEdge 670 server. The Proxmox VE OS is installed on it. The installation was done not through the "Lifecycle Controller", but simply through the image.the iso on the flash drive.
Please explain what options I have to update the drivers, firmware, BIOS on such a server?
Let me write it down point by point so that it's convenient to answer. It will only be about the Dell PowerEdge 670.
As I understand it, there are several options.

1. I downloaded "Dell Repository Manager (DRM)". Then I selected the "Platform Bootable Iso" in it and thus received the .iso file. I recorded it on a USB flash drive according to the instructions via Rufus using the recommended settings.:
Partition Screen = MBR
File System = FAT32
Cluster Size = 1024

Finally. Booted up via a USB flash drive. The installation process has been completed: the BIOS and drivers have been updated.

Then there was a reboot. Then I ran the "Platform Bootable Iso" again to check again for updates, then he wrote that he could not find updates.
a) And here's the question - does "Platform Bootable Iso" require Internet access from the server or not to check for updates? Is it required or not? The problem is that this server is not allowed to access the Internet. And you need to understand the question above.
b) How do I understand that all updates using the "Platform Bootable Iso" have been installed? And is there anything that hasn't been established? How do I see this comparison chart?

2. Then go to "Dell Repository Manager (DRM)" I added a repository for the R670 and selected the OS "SUSE LINUX". Then I selected this repository and selected "Export". And created a "Smart Bootable Iso". I also recorded it through Rufus:
Partition Screen = MBR
File System = FAT32
Cluster Size = 1024

As a result, I booted from a USB flash drive and then everything "stands" on the "Suse Linux" logo and nothing else goes on.
Questions:
a) did I record the image correctly through Rufus? Is DD mode needed there or not?
b) Does the "Smart Bootable Iso" need internet access to work?

c) was it really necessary to choose the SUSE Linux OS (it's just that they choose it on the Internet because of the training videos)? Or is it possible to choose something else? What is recommended?

3. What is the difference between "Platform Bootable Iso" and "Smart Bootable Iso"? What are the differences? I tried to find it on the Internet, but I couldn't figure it out. What a difference.

4. I also tried downloading updates via iDRAC. I chose "Manual", chose "HTTPS" and downloads.dell.com , I chose "PROXY" (I specified a working proxy), but in the end, after 1-2 minutes, it gives an error (I looked at the forum that many people have this problem). Is there any way to update via iDRAC or not?

5. One more question. Since I have not installed the "Lifecycle Controller", its menu items are unavailable. He suggests just installing yourself and that's it. But "Proxmox VE" is already installed. Is there any way to activate the "Lifecycle Controller" without installing the OS through it?

6. If I had "Lifecycle Controller" active, I could download "Dell Server Update Utility, Windows 64-bit format.iso " and upload it to the Lifecycle Controller and install updates through it, while I remind you that Proxmox VE is installed.
That is, the question here is: if Proxmox VE (Debian) is installed, is it possible to install drivers, firmware, BIOS via Lifecycle Controller using the .iso image of Windows (i.e. Dell Server Update Utility, Windows 64-bit format.iso )?

7. What other upgrade options are there?