B.A

Dear,
Please find answer to your queries below:
1. Time-period to apply - Assuming your 12th gets over by March 2019, you should ideally apply by first UCAS deadline of 15th Jan 2019. This way you would be able to apply early and get the decisions early and therefore, well prepared in advance to arrange for finances, accommodation, etc.
2. Exams and documents required - Apart from clearing your 12th exam (ideally with 70%+), you need to appear for IELTS academic test and target a score of 6.0 with no band less than 5.5. Documents required would include 2 recommendation letters from your college, a personal statement, passport copy front and last page, your 10th and 11th results, your 12th predicted score for each subject signed by the principal on school's letter head (you may submit the actual 12th scores when you receive them) and your IELTS score.
3. Details of scholarships available - You will automatically be considered for scholarship along with the application
4. Job opportunities - As per current UK policies, you get a 4 month stay back option in the UK after completion of your UG studies. In these 4 months, you need to secure a job else you will have to come back your home country.
I hope, it will help.