I once made letslearnchinese.org. The apps on this platform will help Chinese language learners build up concepts, especially about characters. It won't walk you through exercises step by step, but it does give hints.
Let me show you the concepts needed for learning Chinese characters. If you'd like to practice these concepts, try letslearnchinese.org. You can get started with strokes for free.
- Strokes.
There are about 28 strokes. Just like the alphabet consists of 26 letters, Chinese characters consist of only 28 strokes. Some people argue there are a little more, some a little less. That's because sometimes a stoke gets deformed based on its place inside a character. Some people count deformations as new strokes, some don't:

All Chinese characters are composed out of these strokes. Our app will show you a character and a stroke. If you can find the stroke inside the character, you can trace/draw it on the character. It works especially well on the phone. It will teach you in what direction to draw the stroke too. If you make a mistake, the app will show you how to draw the stroke on top of the character. It's free, you do need to make an account, though. Otherwise, keeping track of your progress using spaced repetition is impossible.
We wrote a book about it too. Download it here for free: https://letslearnchinese.org/file-downloads/?secret=2bae52bfb3b335eeb25dea53e2bafa7bce0879f2c7e5616273dba9b2268326fc1cf84b15abeb1f8b
- Character components.
Most people tell you about radicals only. But actually, there are two kinds of character components: radicals, and what we call "single characters." Both radicals and single characters are components seen inside Chinese characters repeatedly. The difference is that radicals don't mean anything. They're just that, components. But single characters are characters on their own and thus have meaning. When a single character acts as a component inside a Chinese character, it'll sometimes even hint about its pronunciation. If you know these 100 components, you'll recognize about 80% of all Chinese characters:

You can find single characters in blue and radicals in brown. These are only the most common character components, not all. We advise learning the most common components first. Because you'll be able to learn full characters sooner, when you spot a not-common component later on, you'll easily recognize it anyway since you know all the strokes. This way, you'll learn faster.
Our app will show you a component and a character. The components are missing from the character. You need to draw the component inside the character. The app gives hints about stroke order and direction.
If you're familiar with Chinese pronunciation at this point, you can now start memorizing Chinese characters. They will look familiar to you now because you know the strokes and components of the character. You need to match the characters with pictures (meaning) and sound, and that's it!
Try to learn the most common characters first. Multiple characters together can be used to form words. Our third step teaches the 400 most common Chinese character characters. These characters can be used to create around 1600 words!
That's a little how-to on how to build up concepts when learning Chinese. Letslearnchinese.org might not be as extensive as Codecademy, it's extremely difficult and time-consuming to create, but it would be a great next step!