Hi, welcome to BYOAC!
I thought I'd have a go at helping you - been a few days and nobody else has responded.
Where are you up to? Have you managed to actually start any games with WinUAE? For now I assume you've managed this OK.
Once you have got the WinUAE configuration right, make sure you remember to SAVE it. This will generate a [name].uae file. Keep all your .uae config files in one folder, let's call that "configurations".
Now go to Attract-Mode, press tab to open up the setup menus, go to emulators/WinUAE (or setup a new emulator for WinUAE).
Set the "Rom Path" to be your configurations folder, for example:
C:\Games\winuae\configurations
Set the "Rom Extensions" to ".uae".
Set the "Executable" to be your WinUAE main program file, for example:
C:\Games\winuae\winuae64.exe
Set the "Command Arguments" to:
-config="[rompath][name].uae" --fullscreen
Have added screenshots to help. Sorry about the glare, can't help it at this time of day. Screenshots are taken from my arcade cab with 15khz CRT monitor (converted RGB TV). Layout is the default "Basic" layout.
So far I only have two Amiga games setup (Paradroid 90 & It Came From the Desert), favourites I used to play with my mates back in the late 80s/early 90s. I'm not really a WinUAE expert! Paradroid 90 is brilliant to play on a cab with joystick. It Came From the Desert is a bit clunky but works fine - much like it was on the Amiga originally anyway lol.
My games are setup to run from floppy disc images - If you want to emulate lots more Amiga games, or games with many discs, you probably should explore the Amiga WHDload as well (which will run games from virtual hard drive). The process for setting up Attract-Mode should be identical.
If you want to know more about setting up WinUAE, I suggest you start by watching some of
MikeyGRetro's videos on YT.
Hope this helps.