Hi @Rosie2018,
Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you with us.
Timber can be anchored to brick walls through the use of masonry anchors, typically sleeve anchors or screw bolts or by using threaded rod in conjunction with a chemical anchor such as ChemSet 101.
If you were looking to use the timber as an attachment point for a shade sail, it would be worth speaking to an engineer for their assessment as shade cloths are subject to live loads that the brick wall might not be capable of supporting. An engineer will be able to design a method of attachment that is suitable for your shade sail.
If you had some more details of your plans, and maybe some photos you could share, I would be happy to offer further advice.
Let me know if you need a hand uploading images, I'd be happy to help.
Jacob
