I couldnt find any instructions on this official site from react navigation. In the web (for example YouTube) you can find some "small" tutorials for react native with expo.
I also would like to know if the current implementation/design for the bottom tabs will be repaced by the liquid glass design permanently. Is there somewhere a statement by the react native team?
React Navigation doesn't use the native tabs instead it uses JS Tabs to mimic the behaviour of the native tabs. If you want liquid glass tabs you need to use react-native-bottom-tabs library to replace React Navigation Tabs with Native Tabs. You then need to do a pod install to do the linking and you should be good to go