Hi JoJo! Welcome to the site!

That you are lost in a parking garage suggests you feel confused, or distracted in some area of your life.
Cars (vehicles) usually symbolizes our passage through the journey of life. The way that you travel through your life's journey, and your effectiveness in controlling your life.
The type of vehicle will give indications of the type of experience being related in the dream message. For instance, an ambulance will indicate a need for healing in the giving and receiving of experience, a police car will signify the need for discipline in experiences, an old car might suggest old habits, or 'things the way they used to be' or the need to change the old way of doing things...etc.
The stranger (if he is completely unknown to you and doesn't remind you of anyone you know) is an unknown aspect of yourself. That he helps you suggests that it is you more logical and stronger side.
Doorways represent new opportunities. But that they lead you to all different places suggests a sort of maze. That you are confused about something, or are being mislead.
Red is an active, affective color, full of passion and emotion. It may symbolize passion, luck, joy, happiness, energy, action, sexuality, revolution, warning, danger....but also hate, anger, sin, greed, irritability and will power. As the color of blood, red is also the symbol of life.
A softer red is a symbol of love, mercy and compassion.
Light red stands for warmth and affection.
When intense, red can also indicate hatred, sin, rage.
Dark red is a symbol of passion, greed, energy and anger.
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Is there something in your life that is causing you stress or anxiety?
Is there something that you feel lost, or confused about?
Have you been offered an opportunity of some kind, but you're not too sure it's an honest one....that you are being mislead?
Are you feeling overwhelmed by something, but part of you knows you can overcome the difficulty?

Hope this gives some insight. Good Luck!