Mornings go wrong at the same three points in most houses
Ask ten families where the morning breaks and you get a narrow set of answers. That consistency is useful, because it means the problem is structural rather than particular to your child.
Waking
Little can be done here except the night before. Families who fix mornings almost always fixed bedtime first, and the fix was usually earlier by fifteen minutes rather than an overhaul.
Dressing
This is the movable one. Clothes chosen the night before remove a decision from the part of the day with least capacity for it, and the choosing itself goes better in the evening, when nobody is late. It is the single change with the highest return.
Leaving
The exit is a transition like any other, and it fails for the same reason others do: no warning, or a warning given while the child is mid-task. The same two-minute rule applies here as at bedtime.
Fix the evening to fix the morning. Almost nothing done between seven and eight helps as much as something done at seven the night before.