Stencil is not a framework, its just a compiler that turns classes with decorators into standards-based Web Components. This means that you can generate a collection of stencil components and use them in Angular, React, Vue or Polymer without any problem.
Basically, Stencil combines some of the best features from traditional frameworks, but outputs 100% standards-compliant Custom Elements, thats why you have @Component (Angular), render method (React)…
To make your first component i suggest to read the docs about your first component. You have everything explained there 🙂