As I have never taken a holiday on my own, I am a little nervous and would be grateful for any information.

I did this trip last year and enjoyed it very much. There is a review here https://forum.justyou.co.uk/Posts/t127042-Treasures-of-Andalucia---2-June-2022  

As for getting to the beach I did not do this myself as I did all the excursions which only left me one day which I spent exploring Mijas. There are local buses and some people used these and found it easy to get around using these. It is quite a walk to the beach and coming back is all uphill!

If you are just after a swim the hotel does have a pool.

Anything more specific then do feel free to ask.

Ian