Test preparation

Get in line with the Business side of the daily news articles. Be well informed politically and know what and where you want to be in near future.
Forget about how things run in an IT company and come with a blank frame of reference. Try to learn some finance basics if interested in finance.
Basically just being well informed in every day's who's who and political knowledge should be a good starting choice

attend coaching classes which is available in Delhi because exam is 2 difficult without coaching

it is up to you and also how strong your fundamental skills are . I personally think, 11th is a bit early to start coaching. the syllabus for the foundation level in CS is manageable without coaching provided that you have a good commerce background. just look at the syllabus and decide for yourself.

Go for arihant publication books

Physics is a very tangible subject. You can actually see everything happening around you. When we are not good at something it represents our disinterest in that thing. Try to develop your interest in it by strengthening your concepts. Solve the easy questions first. I recommend you use the book HC Verma. After every chapter it has concept based questions which are the best to test whether you really understood the topic.

CA is the one of the most difficult course of commerce
It is also highly respected and good professional course
Ca can work in auditing , taxation and various matters like valuation , merger, credit rating
There are 3 levels CPT, IPCC and Final
CPT can be pursued after 10+2
IPCC can be pursued directly after graduation
It also requires 3 and 1/2 years articleship training uder practicing CA/CA firm