Hello @Jeyversee
Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your kitchen tap.
If you look closely on your first photo you will notice a little silver cover cap on the right-hand side of the body of the tap. It may look like a water droplet but when you put your finger on it it is a raised cap very well disguised. I suggest removing this cap cover and getting an Allen key to remove the grub screw. If the grub screw is worn out, I suggest replacing it with a generic one from this packet - Pinnacle M5 - M8 Black Assorted Grub Screw Set - 12 Pack. Once you find a similar one put the spout back into place and screw the grub screw back into place to make sure that you can't lift the spout out. Please remember to put the cover cap back on.
If you have any other questions we can help with, please let us know.
Eric