The PoodLL zip file is  a bit larger than most other plugins at nearly 60MB. If you try to drag it into the file upload area, and the border turns red, or if you try to choose it and get an error message about the file size, then you will need to increase your site's maximum upload size. See the Moodle docs here, for how to do this:  https://docs.moodle.org/en/File_upload_size