Reiki is universal energy being used to heal those that may need it. This is an ancient practice that has been around longer than we know. It's something that brings you comfort and is an alternative healing technique that is natural and etheral.
There are many ways to practice healing and Eyem not here to teach but to inform. There's no true origin to this but there are many practitioners that follow the westernized teachings.
You can have Reiki sessions performed on you in person and this would consist of the practitioner forming energy within their hands, setting certain intentions for your healing, and scanning your energy centers.
There are also Distanced Reiki sessions that can be performed in many ways. This is a great option for those that don't have these services in your area.
If Reiki is something that interests you we do offer free Reiki sessions. Feel free to check this link out divinebrujita.com/reiki