You need to secret squirrel naproxen but you can get paracetamol with codeine with no script, but you do need to have a conversation with a person behind the counter first (or online with no conversation!) . Funny quirks.
As someone who's taken a fair bit of naproxen (on prescription) for lupus, I would definitely recommend you take it on a full stomach as it can be really harsh on the stomach.
I also need to take anything with phenylephrine hydrochloride, paracetamol, diclofenac, guaifenesin, or ibuprofen on a full stomach or I puke
Everyone should read the leaflets that come with whatever medication you take and take sensible precautions. Always worth a check with a pharmacist or GP if you want to take something for longer term or off-leaflet.