You can add a Progress Bar to your App under Settings > Styles.
By default, the progress bar only increments by 5% on each Page Block. This means, under the default configuration, the progress bar never reaches 100%.
You can manually override the progress % on each Page Block:
The typical pattern we see is the App author will hardcode the % on just a few blocks, so maybe 0% on one Block, 25% on another, 50%, 75%, and 100% for the Final Block. Any blocks in between those with the hardcoded progress value will simply increment 5% on top of that hardcoded value.