The idea of hybrid development is you can build your app by programming only once without the need to develop for each platform (Android or IOS). As you yourself mentioned, there are several options. such as Cordova/Phonegap, Ionic or React Native.
For hybrid development, good knowledge of javascript is required.
If you use Cordova/Phonegap, you can develop in HTML, CSS + Javascript.
If you use IONIC, you will also use HTML, but the programming is in Angular/Typescript
Finally, if your choice is React Native, you will not use HTML and CSS, the layout is done differently. The programming is in Javascript.
A difference between React Native and the other two is that in the case of React Native the layout is native, ie when compiling the application is creating a native layout of the platform, coupled to its programming in javascript. In the other two, when compiling is creating a webview and your application runs within it. React ends up requiring more effort, but performs better.
Although the code is unique, you may need specific settings for Android or IOS.
Here are some links to help you better understand these platforms:
https://rocketseat.com.br/starter
https://loiane.training/curso/phonegap-apache-cordova
https://tekzoom.com.br/ionic-framework-documentacao-e-aplicacoes-completas-para-download-gratis-video-02/
so it really doesn’t use any back-end java language, python Swift, Kotlin
– user111361