I made some progress on the level progression and the lives system today.
I used PlayerPrefs (although I’ve read that PlayerPrefs might not be the optimal way to save player data) to keep track of both of them. Now, the level select screen shows if the player has already completed the level or not and the number of lives persist after a level completion. However, the player can still select the completed levels, I’ve still yet to fix that.
I will also be recording my progress and also to show some gameplay footage, however it’s already quite late so I might just do that tomorrow.