Does he use the internet? I would imagine there are lots of elderly people in the same boat but they just don't know how to meet each other. Maybe Age UK'd know something.
Mind, I never even succeeded in teaching my mother how to text. Despite frequently revised written comprehensive instructions. She had this damn fool saying "You can't teach an old dog new tricks". And I'd respond "You can if the old dog wants to learn". She'd laugh hilariously. She's gone now. I'm glad. What with that virus crap around. It must be really stressful for you.
Don't bring him here - some callous idiot might accuse him of virtue signalling. That would hurt him. Extraordinary how compassion has suddenly become something to be ridiculed. God, it really is a sick society we live in.
Make sure you get the rest of the family involved in looking out for him. A phone call, a letter/email, whatever. You don't want the entire burden on yourself.
Stay safe, the both of you.
Good luck, Jackie.