Hello
@Doons and welcome from me too.
My dad used to be like this bug one trick I found worked for him was to put the shower on and then pretend he'd intended to get into it all along. This did mean that I'd have to get to his house before he'd got dressed but in my dad's case he wasn't an early riser so if I was there by 9.30 after I'd dropped the kids off at school I could persuade him.
To be honest if I got him to have a shower once a week it was an achievement. But as long as he didn't smell too bad I tried not to worry.
My dad's generation grew up with bath night once a week and soap and flannel inbetween.