I’m not an expert in back ups, and it’s a bit off-topic here, but suggestions (any of which may be a solution)
- Search the forum for suggestions (not sure whether this has been tackled recently)
- Manually copy all the files in /data/media (e.g. photos) and use TWRP for the rest - there’s a recent guide here.
- Look into MyPhoneExplorer (warning: proprietary software), which seems to be a popular choice amongst veteran forum members.