I don’t know your game… so i can’t give you the right code that suits your project, there are different possibilities.
Do you have a level select menu? Should it change the level directly after the app start?
What exactly do you want to save when? e.g. the highest unlocked level when a level is finished…
Sorry, it just means the value is increasing, that it has another number added to it.
I don’t understand why you are parsing it, unless it’s a structure. You should just write the value to storage, and read the value from storage. No need to parse if it’s just the number that you’re saving.
So the read process should be "Read from storage into a scene variable" and "copy the scene variable value to the global variable". And the write process is just "write the variable to storage".
But, since you are reading from, and writing to, storage, you can just use the scene variable and not use the global variable.
Also, make sure you’re reading and writing a number, not a text/string.