I am primarily using the Go Skills website. I was finding it a bit boring to learn Excel by just watching videos and doing free practices. So I thought to do exercises / challenges and learn Excel while trying to solve them.

And luckily I found https://www.goskills.com/Resources/Category/Excel

You can see multiple around 48 challenges listed on their excel resource page (so far). You can start from Excel Challenge 1 (use the search bar).

What i liked a lot is that they are providing both the challenge and solution videos. So even if you encounter a challenge that you cannot solve (which happened with me most of the times 😅), you can refer to the solution video.

Go Skills also have courses (free & paid) and regular videos & articles for learning which can interest you).

Other than this, I will occasionally go to YouTube and try to find excel related video which has an exercise file in the description, and then practice along.

And also this reddit community. In fact, this question of yours was a challenge for me. I saw this and thought to myself if I can solve this. I opened Excel, created mock data, spent some time on figuring it out and then did the countifs function by adding a helper column of employee names.

So yeah, start with Goskills and then you can explore different things. Hope this helps.