Installing Windows on Lenovo Legion Go S (Steam) How to:
I saw a lot of people trying to do this, I just went through it, was really simple. Just need a laptop:
Runs smooth.
What you need
You’ll want:
• a USB flash drive, 8 GB or larger, for the Windows installer
• your external hard drive or a second USB/microSD for Lenovo drivers
• a USB-C hub or dock so you can connect power and USB storage at the same time
• your charger connected during the whole process
Microsoft’s Media Creation Tool writes the Windows installer directly to the USB drive you choose. 
Files to download before you start
On another Windows PC, download:
- Windows 11 installer
Use Microsoft’s official Media Creation Tool from the Windows 11 installation media page. 
- Lenovo Windows drivers for Legion Go S 8APU1
Lenovo’s support pages list Windows 11 driver support for Legion Go S 8APU1, including the AMD Chipset Driver and Legion Space Application. 
At minimum, download these from Lenovo support for your model:
• AMD Chipset
• AMD Graphics / VGA
• Wi-Fi
• Bluetooth
• Audio
• Legion Space
Step-by-step: make Windows your main OS
Step 1: Create the Windows installer USB
On another Windows PC:
1. Plug in your 8 GB+ USB flash drive.
2. Open Microsoft’s Windows 11 installation media page.
3. Click Download now under Create Windows 11 Installation Media.
4. Run MediaCreationTool.exe.
5. Choose Create installation media.
6. Select your USB drive.
7. Let it finish.
This will turn that USB into a bootable Windows installer and typically wipes/reformats that USB in the process. 
Step 2: Save Lenovo drivers to your external drive
On that same PC:
1. Create a folder like Legion Go S Drivers
2. Put all downloaded Lenovo driver files there
3. Safely eject the drive when done
Step 3: Power off the Legion Go S completely
On the Legion Go S:
1. Shut it all the way down
2. Plug in:
• the charger
• the Windows installer USB
• your external drive with the Lenovo drivers, if your hub allows it
Step 4: Open the boot menu
Lenovo’s SteamOS install instructions for the Legion Go S say to enter the startup menu by holding Volume Up and then pressing Power, then choosing Boot Menu. 
Do this:
1. With the device off, hold Volume Up
2. Press Power
3. When the startup screen appears, choose Boot Menu
4. Select the Windows USB installer
Step 5: Start Windows Setup
Once Windows Setup loads:
1. Choose your language and keyboard
2. Click Install now
3. If asked for a product key, choose I don’t have a product key if you want to activate later
4. Pick the Windows 11 edition you want
Step 6: Choose a clean install
When asked which installation type you want:
1. Select Custom: Install Windows only
That is the option for a fresh install rather than trying to preserve the existing SteamOS setup. Microsoft documents installation media as a way to install Windows on a device that does not already have Windows installed. 
Step 7: Delete the existing SteamOS partitions
This is the part that makes Windows your only OS.
On the drive selection screen:
1. You’ll see several existing partitions on the internal SSD
2. Select each internal drive partition related to the current SteamOS install
3. Click Delete
4. Repeat until the internal SSD shows mostly or entirely as Unallocated Space
Then:
5. Select the large Unallocated Space
6. Click Next
Windows Setup will create the partitions it needs automatically.
Important: only delete partitions on the Legion Go S internal drive that belong to the existing install. Do not delete your external drive or installer USB by mistake.
Step 8: Let Windows install
Windows will now copy files and restart several times.
Just let it run. If it reboots back to the installer once, remove the USB after the first restart or choose the internal Windows boot entry from the boot menu.
Step 9: Finish first-time Windows setup
Go through the normal Windows setup:
• region
• Wi-Fi, if available
• account setup
• privacy settings
If Wi-Fi does not work right away, that is not unusual before drivers are installed. Use the Lenovo Wi-Fi driver from your external drive once you reach the desktop.
Step 10: Install Lenovo drivers
Once you’re on the Windows desktop, install your saved Lenovo drivers.
Use this order:
1. AMD Chipset
2. AMD Graphics / VGA
3. Wi-Fi
4. Bluetooth
5. Audio
6. Legion Space
Lenovo officially provides at least the chipset package and Legion Space app for the Legion Go S 8APU1 under Windows 11 support. 
Restart when prompted.
Step 11: Run Windows Update
After the Lenovo drivers are in:
1. Open Settings
2. Go to Windows Update
3. Check for updates
4. Install everything available
5. Restart as needed
Step 12: Enable the on-screen keyboard
For handheld use, this matters a lot.
To keep the touch keyboard easy to access:
1. Open Settings
2. Go to Personalization
3. Open Taskbar
4. Turn on Touch keyboard
Microsoft also provides a full On-Screen Keyboard under Accessibility if you want a persistent keyboard option. 
Step 13: Install your apps
Now install what you actually want:
• Steam
• WeMod
• Xbox app / Game Pass
• Epic, Battle.net, etc.