Hi
@Dottiedog I would also consider a move into care. Not all care homes are alike and a search should find one that will give your dad a bit of independence at the moment if that is appropriate and then more support as his needs progress. I would be wary of supported accommodation, even with extra care. It could be fine for your dad now, but not suitable in a few months time. Certainly that is what we intended for my mum until we realised it just wouldn't work. I'm assuming from this that your dad will be able to fund his own care from the sale of his flat and any other assets he has. If not then you will need social services to help you make decisions.
This site
Care Home UK is good for drawing up a shortlist. Reviews and reports are a useful guide, but nothing beats actually going and have a look for yourself.
I don't know if this fact sheet with help with some of the other decisions that you will need to help your dad make.
Alzheimer's Society can help you access the right support and plan for the future after being newly diagnosed with dementia.
www.alzheimers.org.uk