Angular comes in the class of frontend frameworks called SPAs (Single Page Applications). These are a class of frameworks where the entire frontend project is usually compiled in a single page and shipped with relevant JS / CSS bundles. Although you as a user may feel the routes changing eg, /about /contact-us, the routing is done by the index.html and not by any backend server.
Using frontend frameworks and not vanilla js pages is the preferred way to build complex frontend projects. Angular is a lot more structured than react and is therefore our framework of choice.
Using Agular, we can re-use components of a web page in different locations and add significant "Brains" to the frontend of the site.