First of all welcome to Riviera Travel. We definitely understand that the first solo trip can be quite daunting, and so I think the Bruges Solo break is a good choice to test the waters. Not only is it short, but since travel is by Eurostar you can book tickets from a regional railway station of your choice with us, thereby removing (almost) all the travel hassle.
With regards to the age range of our groups most of our clients are in their 60's and 70's although there are many both younger and sometimes older too. However age tends to get forgotten on tours and people find kindred spirits across generations.
I hope you will be able to find some tips and reassurance from our other forum users here. And if you have any questions don't hesitate to ask.