How to measure my door

mg src="https://cdn.shopify.com/s/files/1/0849/1456/t/8/assets/furniture-table-interior-floor-flooring-wood-chair-window-diagram-parallel-pattern_330.jpg?7455203267589553094" alt="How To Measure My Door" data-original="How_To_Measure_Your_Door_grande.png" data-ai="true"