How to work with local storage in a web app

Hello folks!

I am very new to ionic and developing my first application. This application will be only for personal use. Hence I will have to use it as a web app and not publish it on the app store.
There will be CRUD operations and I’m now looking for a way to handle the data in my ionic app, which should be serverless, so the app can be used offline.
And I’m really not sure what is the recommended way to do this in ionic. When you google, most results involve a cordova plugin, but my app will never be compiled to an actual app, so I think this will not work for me?

My first try was to use @ionic/storage as described in https://ionicframework.com/docs/building/storage. But how would this work with more complex data? How am I supposed to retrieve the id of a record?

Thanks in advance!

(using ionic 4 with angular)