ok. The first thing you need to do is to add all your music folders in the Collection section in Strawberry's settings. Something like this:

Add all your music folders and let Strawberry scan your files. It will take a long time, but it won't need to be done again.
Then you should create a 'Smart Playlist'. From what I gather, you need specific folders in your different playlists. For that, follow these steps:
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On the left side ribbon, below 'Playlists' you should see 'Smart Playlists'. Click on it and you should see a 'Plus' button:

Click on it (see the mouse pointer next to the Blue folder icon)
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It should open a window like this:

In the 'Search Terms' section, you can add 'rules' to search files based on a variety of terms. The 'File Name' rule scans the full path of the files, including folders. So if your folders are in the collection of Strawberry and the scanning is complete, it should pick up any songs that match your search.
After adding your search terms, you can see the songs found in the bottom section of this same window. Then just click next until you reach the end and just enter a name for this playlist. You're done.