My mum sold her house and bought something very similar (maybe even a bit longer!). She travelled all over the UK and Europe, wintering somewhere lovely and warm like Spain. She had never driven anything like that before, learnt how it all worked and how to operate everything by herself. Travelled around for about 3 years before circumstances changed and she sold it.
She had a fantastic time and was well into her 60's at the time. Take a deep breath, have confidence and enjoy!