Hi @Daniel Muscionico
I will recommend you to use SharePoint Framework. The SharePoint Framework (SPFx) is a page and web part model that provides full support for client-side SharePoint development, easy integration with SharePoint data, and extending Microsoft Teams. With the SharePoint Framework, you can use modern web technologies and tools in your preferred development environment to build productive experiences and apps that are responsive and mobile-ready.
Please refer to following steps to setup your tenant and environment
https://learn.microsoft.com/en-us/sharepoint/dev/spfx/set-up-your-developer-tenant
https://learn.microsoft.com/en-us/sharepoint/dev/spfx/set-up-your-development-environment
And refer to following steps to deploy a spfx webpart
https://learn.microsoft.com/en-us/sharepoint/dev/spfx/web-parts/get-started/build-a-hello-world-web-part
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