In such cases, while it is often described that the space between the eyebrows glows, that seems to be a state that occurs towards the end of meditation. Instead, I feel that light or energy, or an aura, first gathers around the space between the eyebrows, and then gradually narrows its width, moving towards the center of the space between the eyebrows. It feels like waves approaching the shore of an island, or like a castle built on sand gradually being submerged by water, penetrating towards the center.
And, in addition to that, it seems that energy flows from the area between the eyebrows to the body's central axis and the heart, as energy routes that run parallel to each other pass through the areas around the eyes and the nose in each direction, especially horizontally to the left and right of the nose, and upwards towards the cheeks.
The energy received from the space between the eyebrows flows throughout the body. Therefore, not only the energy route from the space between the eyebrows to the center of the head, but also the nose, which is a place where the ida and pingala, the body's left and right energy routes in yoga, are connected, is an important area to focus on.
By doing so, not only are the body's left and right energies activated, but the heart (anahata) is also activated. I think so.
Before meditation, the face may appear blurred due to a lack of energy. However, by focusing on the space between the eyebrows and the left and right sides of the nose, awareness becomes clearer, and the face becomes more vivid. I think there is such an effect.
It would be even better if the Sahasrara at the crown of the head opens, but even if it doesn't, I think it's good to focus on these basic areas first. I feel that I often have the Sahasrara open, but in daily life, the surface of the face tends to be blocked, so I need to focus on opening it during meditation. This may vary from person to person.