It’s easy to start developing UXP-powered plugins for Photoshop. You’ll want to check some of these links out to help start you on your journey:
- Photoshop & UXP Docs: https://www.adobe.io/photoshop/uxp/
- UXP Developer Tool: https://www.adobe.io/photoshop/uxp/devtool/
- Plugin Samples Repo: https://github.com/AdobeDocs/uxp-photoshop-plugin-samples
Be sure to download v22.0.0 of Photoshop from the Adobe Creative Cloud Desktop application. Then go into Preferences > Plugins and 
Enable Developer Mode. Restart Photoshop and launch the UXP Developer Tool and start loading and debugging your plugins!