SPFx
https://docs.microsoft.com/en-us/sharepoint/dev/spfx/set-up-your-development-environment
1) Installer Node
2) À l’aide de l’invite de commandes (command prompt), installer gulp, yoeman et SharePoint Framework Yeoman Generator
npm install -g gulp
npm install -g yo
npm install -g @microsoft/generator-sharepoint
https://www.c-sharpcorner.com/article/build-custom-app-pages-with-sharepoint-framework/
3) Visual Studio Code
https://code.visualstudio.com/?wt.mc_id=vscom_downloads
Hello World WebPart