CS5 is discontinued & unsupported. It's never been tested on Win11 and never will be.
We can make no guarantees it will work on your system.
You can gamble & try it or just hold on to Win10 until you're ready to replace with modern software.
MODERN OPTIONS:
Photoshop Elements or Premier Elements (approx USD $100, no subscription needed).
https://www.adobe.com/products/photoshop-elements.html
Creative Cloud Photography Plan (approx $10/month for 12 months). Includes the following:
- Photoshop CC and Photoshop on iPad
- Camera Raw
- Lightroom on desktop, mobile and the web
- Lightroom Classic
- Portfolio website + hosting
- Adobe Express (free starter plan)
- Bridge
- 20 GB cloud storage (upgradable to 1 TB).
https://www.adobe.com/creativecloud/photography.html
Premium Adobe Express ($10/month).
- Creative Cloud Express app (web and mobile)
- Premiere Rush (desktop and mobile)
- Photoshop Express (mobile)
- Spark Video (mobile)
- Spark Page (mobile)
- Adobe Portfolio + hosting
- 100 GB of cloud storage
- All premium templates and design assets including the entire collection of over 160 million royalty-free Adobe Stock photo collection.
https://helpx.adobe.com/express/using/express-overview.html
Creative Cloud All Apps (51 + apps & services) and Single Apps Plans
https://www.adobe.com/creativecloud/plans.html