Hi @tom555
As far as I am aware there are no official guidelines for naming conventions for apps, flows, solutions or tables. The key thing is to make sure that the names are meaningful and make sense to you as a maker and other people in your organisation who will be viewing these components.
For flows, a common standard is prefix the name of the flow with the name of the feature or business area so that similar flows are grouped together in a list. Take a look at how they do this in the CoE starter kit.
For tables, make sure that you create them within a solution that has a publisher with a meaningful prefix.
If you have a lot of solutions, sometimes it is a good idea to prefix the name of the solution with the business unit name or have a separate publisher for each business unit.
A lot of this really depends on your organisation and how people work together on the Power Platform. I wouldn't get too hung up on this but maybe spend some time with your team and define some basic naming conventions that make sense for you.
