The Sanskrit word Tantra means "continuum" or "flow," and refers to a highly refined science that harmonizes the human consciousness with the subtle and powerful forces at the base of life.
“In the view of Tantra, the body's vital energies are the vehicles of the mind. When the vital energies are pure and subtle, one's state of mind will be accordingly affected. By transforming these bodily energies we transform the state of consciousness.” - The 14th Dalai Lama
Here are some courses, books, and articles to get you started: