The Tantric force is transmitted to the initiates of the tantric masters who also tells the secret learn about how to use the tantric force. Force can be used to attain salvation (moksha or nirvana) and magical abilities (siddhi’er).
Tantra can act as a “right-handed tantra” = white tantra, which is neither sexual nor prohibited, but only occult and symbolic.
Tantra can also act as a “left-handed tantra” involving sexual techniques = red tantra.
Or tantra can, in rare cases downright contain prohibited items such as incest, necrophilia and human sacrifice = black tantra.
Yoga is an Indian training of the body to produce one’s salvation or magic abilities.
The original yoga consists of ascetic and moral life and body training using meditation and breathing exercise.
Later yoga forms – such as Hatha Yoga and Kundalini Yoga – are tantric and eg. the extreme stretching exercises (asana’er), which most people associate with yoga.
But the tantric yoga may also include meditation with visualizations that you hold your breath, that you rapidly fair mantras and having ritual sex by withholding ejaculation and get an ‘introverted ‘ orgasm and ejaculation.