You could implement something like this

First run

npm i @react-native-async-storage/async-storage

And then create a AsyncStore.js or similar file:

import AsyncStorage from '@react-native-async-storage/async-storage';

export const storeObject = async (object) => {
  const id = await createId()
  const identified = {...object, id }
  const jsonValue = JSON.stringify(identified);
  await AsyncStorage.setItem('@object-' + id, jsonValue);
};

export const getObject = async (id) => {
  const storedObject = await AsyncStorage.getItem('@object-' + id);
  if (storedObject){
    return JSON.parse(storedObject );
  }
};

export const storeIds = async (ids) => {
  const jsonValue = JSON.stringify(ids);
  await AsyncStorage.setItem('@object-ids', jsonValue);
};
export const getIds = async (id, ids) => {
  const storedIds = await AsyncStorage.getItem('@object-ids');
  if (storedIds) {
    return JSON.parse(storedIds );
  }
};

const createId = async() => {
  const ids = await getIds();
  const id = Math.max(ids) + 1
  await storeIds([...ids,id])
  return id;
}

Edit: I added some untested unique identifier code