The bright glowing ring surrounding the black hole is known as the accretion disc.
The accretion disc is a superheated cloud of gas and cosmic dust spinning around the event horizon.
The gravity inside of a black hole is too powerful for any light to escape past the event horizon.
But the accretion disc itself is immensely bright and releases vast amounts of electromagnetic radiation, such as x-rays, radio waves and infrared beams into space.
The dark black hole like spot is NOT the black hole itself, It is a dark, round shadow, which is the black hole's event horizon.The event horizon is the point of no return, past which all matter, including light, falls towards the black hole’s infinitely compressed singularity.