You don't need a referral from your GP (or other healthcare professional) to see a psychologist at My Brain Space.
Although, if you require or are entitled to a rebate, you may need a referral from your GP.
To access a Medicare rebate, you will need to speak to your GP about a mental health treatment plan (this includes DVA card holders).
Self-Managed NDIS clients do not require a referral but they will need to ensure their funds will cover the psychologist appointment.