Yes, if you fail in Physics but pass all other subjects including Chemistry, Biology, Painting, and Computer Science (your additional subject), you will still be considered to have passed 12th grade under the CBSE board.

According to CBSE rules, you only need to pass five subjects to be considered passed in 12th grade.

Even though you are taking Computer Science as an additional subject, your result in that subject does not affect your overall passing status.

If you want to improve your Physics grade, you can appear for a compartment exam in that subject later.