First of all, to get this out of the way, I'll start by saying that labels are just words used to describe someone's specificities, but of course no label can define any human being. We are more than a function, a job, a quality, etc.
A healer is a catalyst, a facilitator, someone who helps you launch your own self-healing abilities and eases the process. A healer channels the Source energy, uses their know-how and provides their clients with all the tools and key information that they need in order to help them heal themselves at the energy and spiritual level first to impact the physical body, the mind, etc.
It is important for me to mention that a healer doesn’t heal directly per se, no one has the absolute power to heal someone else - please be careful if you ever came across someone who would pretend that they can heal you and solve your problems for you.
I don't like to refer to myself as a healer, more like a catalyst or facilitator. I channel energy for my clients to receive all the energy and help they may need at this moment, clear their blocks, feed their energy system, etc. so that they can heal their physical, emotional or mental challenges and/or diseases and also their soul.
To conclude, I'll say that it is a team work, no one can "fix" anyone, it is a synergy between the facilitator's will and devotion to help the clients and the clients' will and dedication to heal and take care of themselves, the exchanges are always beautiful.