Based on Buddhism, these teachings and practices are secular, i.e. non-religious.  It is important to understand that Buddhism is and always has been a way of conducting ourselves.  It is an approach to how we live our life and how to find our place and live in the world and in society generally.  Buddhism is not meant to be regarded as a religion to be followed.  In fact, the Buddha expected his followers to try and test out what he was teaching for themselves.  Not just believe what he was telling them.  He never wanted a following as such.

There is no lower or upper age limit.  Whether you are young, middle aged or senior, have a different ethnic background or non-white identity, have a disability, whatever your sexual orientation, whether you are young, at school, working, looking for work, senior, stressed, lonely, grieving, already have a meditation practice, are a non-Buddhist and already have a religion, or you are a Buddhist looking to deepen your practice and how to apply it to everyday life, everyone is welcome and can benefit. 

Also and more importantly, in spite of whatever has happened to you, or you have done in your past, you can always benefit from these ancient tried and tested practices and teachings which start with where you are at NOW!.  Just bring yourself along, no questions asked, you are welcome, wherever you are at, whatever your starting point may be.