I have lots of picture files in my Google Drive accounts for work. I don't understand why those pictures in Google Drive take up "storage", whereas pictures in Google Photos (in high quality) don't. So how can store all those pics in the corresponding Google Photos, and only link them into my Drive subfolders where necessary so they don't take up storage space.
The photos in "High quality" in Google Photos are actually compressed. Google offers you free storage for this setting because they're encouraging people to back up all their photos to Google Photos, without undesirably running out of storage space later on.
If you want your photos to not take up space, with this setting, you will have to import your photos from Google Drive into Google Photos. First, make sure that the upload size is set to "High quality (free unlimited storage)" in the Google Photos settigs. Then, click "Upload" on the top-right of photos.google.com, then select from "Google Drive", and select all the photos in a folder you want to import. Once you have imported the photos to Google Photos, you can choose to delete them in Google Drive, so that they don't take up storage space there.