I want to install this large mirror on plasterboard wall of our living room. Some tips about its installation are mentioned on its back as shown in figure. As I am new to this job, I am in need of recommendation about the specific screws applicable to it.
Welcome to the Bunnings Workshop community @sandeeprai. It's fantastic to have you join us, and many thanks for your question.
Ideally, it would be best practice to screw directly into your timber studs which will bear the 11kg of weight. However, I would hazard a guess that the mounting points will not line up with your stud work. If this is the case, then you could place a bridging piece of timber fixed between the studs and fix the mirror to that.
If you want the mirror flush against the plaster wall, you'll be limited to using the screws provided in products like GripIt 15mm Yellow Plasterboard Fixing - 4 Pack. The screws in this pack appear to suit the limitations of "a head not wider than 6mm and a neck not wider than 4mm". There are no minimum requirements listed, so I would encourage you to test the screws to ensure the heads lock into the mounting plate. If in doubt, please contact the mirror's supplier for further details.
Please let me know if you need further assistance or have questions.
Thank you! I will let you know if I need further help.