Downloading the iso file from the LFSupport site should include a newest available version of all packages. Out of the specific products you mentioned, the only one I think that is separate from the consolidated iso is Connector. It includes a date in the file name so you can tell when it was packaged. For example, I have been working from a package dated 20231219 (2023-12-19) which I downloaded because it included the newest release of LFForms (Version 11 Update 5, which is version 11.0.2311). When you do the Autorun of the iso (or start the Autorun.exe) you'll get a multi-page menu of all products and you can pick and choose which you want to install.
You could also dive into the individual menus of the iso folder structure to find the individual installers. I did this so that I could make a smaller Windows Client install package for sending out to workstations. We only needed English, so from the "en" subfolder, I copied out the "OCR", "Support", and "Windows Client" folders and put those in a separate zip file that I could send to workstations. It was still huge (1.7 GB) but smaller than the full iso. Then after the individual workstations had it downloaded, we could unzip and then run the install from the "WindowsClient" folder (run the "SetupLf.exe" program).
The iso should include all updates. For example, from the Windows Client install I mentioned above, it includes a subfolder named "Updates" that includes all of the hotfixes to get the client from version 11.0.2201 to 11.0.2305 and it automatically applies all of them at the end of the main installation (it doesn't explain it is doing that, but I've run this installer enough times that I can tell it's doing a bunch of hotfixes at the very end of the install, and I've also been able to upgrade a workstation from 11.0.2201 to 11.0.2305 by manually running all the installs from the "Updates" folder).
I can't say for sure it is okay to run the client install on a newer version than the server, but I wouldn't recommend it. I know you can run a lower version client than the server (we've been on server 11 for a couple years, with most workstations still on client 10.3 or 10.4 until just a couple weeks ago), but I've never tried the other way around. This isn't an exact comparison, but I briefly had a newer install of the Workflow Designer on my own machine than I had Workflow Server running on the server, and it caused multiple errors and even Workflows that could not open (and crashed the Designer), so I would not recommend that. Visually the Windows Client hasn't changed much since the 10.3 or 10.4 versions - but there are about a dozen or so iterative changes that have happened since then, and any of those that rely on the server working in a particular way from the newer version could result in the program crashing or having other issues.
The Client installer isn't going to allow client 10 and client 11 to be installed side-by-side. If it detects any prior install, it's going to run the install more like an upgrade than a separate install.
Ability to install on multiple servers is going to be entirely dependant upon your licensing, and you should speak to your Solution Provider about that if you are uncertain. For example, most Avante licenses are going to limit you to a single instance of LFServer, whereas Rio licenses don't have that limitation. And there is a lot more options in the licenses than just those two, so this question is really beyond the scope of LFAnswers to assist with.
Did I miss any part of your questions?