How do I delete an object property with the property name being stored in scope? [duplicate]

I am creating a flag game where a random flag is pulled out of an object and the information is stored in a global scope in order to check if the answer given matches the country name associated with the flag.
I would like to delete this property from the object, but can only manage to delete the property if i give the specific property name. But because it is random i dont know the specific property value. Is there a way I can do this with the scope it is stored in?

let randomFlag = () => {
        let keys = Object.keys(flags);
        if (keys.length > 0) {
            const index = Math.floor(keys.length * Math.random());
              const key = keys[index];
            const value = flags[key];
            return {index, key, value}
        }
        return null;
    };
    const property = randomFlag(flags);
    currentFlag = property.key
    document.getElementById('flag').innerHTML = `${property.value}`;
    delete flags.currentFlag // This is part is not working unless I write the specific property name.