Hi
Welcome to learning Power BI and DAX!
I assume you're getting something like this when you try?
If so, Power BI is treating your Average Number of Hours per Week field as an implicit measure, because it's numeric.
You don't want to change this behaviour, as this is a good candidate for other calculations, but you can change this for the visual that you want to group it in.
In the fields list, click on the caret (down arrow) next to Average Number of Hours per Week and select Don't summarize, e.g.:
This will tell the visual to group by the unique values rather than aggregate them, and this should give you what you need, e.g.:
Hopefully this should be all you need to proceed.
Just to let you know, if you have any further questions specific to DAX, then it's generally better to post them in the DAX Commands and Tips forum, as it is a lot more heavily frequented than this developer forum and you'll get a much faster answer. The DAX folks don't look in here too often 😉
All the best,
Daniel
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