Safe to use this bike? Bought it years ago and finally got around to trying to restore it- mid 60s Raleigh Superbe- but realized it has a pretty sizable dent in the frame

I can’t tell if that tube is split. I’d say if its not cracked I’d be riding it around town without major concern. Not sure that I’d want to do loaded touring on it but hitting the pub or getting some supplies, sure.