The Gita's teaching about the soul begins early, in chapter 2, and returns again and again. The soul, or atman, is the conscious self: unborn, imperishable and distinct from the body and mind. For many readers this teaching brings steadiness. It suggests that our deepest identity is not at the mercy of events, and that death and loss are transitions within a larger continuity.
Gita 2.20 says the soul is never born and never dies, and remains unchanged, ancient and eternal even when the body perishes, so use this knowledge to face fear, grief and the prospect of death with calm courage. Gita 2.22 compares death to changing worn-out clothes, and Gita 2.13 compares changes of body to the stages of life. Gita 2.12 says the individual self was never non-existent and will never cease to exist, which can steady us through change.
The Gita also speaks of unity and the witness. Gita 5.18 says true wisdom recognizes the same spiritual essence in every living being, and Gita 6.29 describes the perfected yogi seeing the same Self in every being, so treat all people with respect and dignity. Gita 15.7 says every being is an eternal part of the Divine, and Gita 5.13 describes the Self as a non-acting witness within the body, so avoid identifying your true self solely with roles, achievements and activities.