Is cesium similar to google maps and how can one display custom 3d objects on cesium with geo cordinates?

Is it possible to display custom 3d objects on cesium map with geo coordinates lock such that user can zoom as well rotate them

If you have your own 3D models, you can upload them to Cesium ion to host them and display them in your CesiumJS map. Make sure to check out the getting started guide:

https://cesium.com/docs/tutorials/getting-started/

You can also create geometry types on the fly, check out the code examples this this polygon one here:

https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Polygon.html&label=Geometries