Hospitality Management

Yes, definitely,
There are colleges which offer Travel and Tourism specialisation. Its one of the best industry and you can just complete your 12th and join this course. In Garden City University we have a course for Tourism and it's BA in tourism (Hons). Please check the website www.gardencity.university It's one of the top universities and the best course and training is given here.

There is no compulsion as such. You can pursue any course in Masters.

Basically, it completely lies on your interest.
For Bcom graduate, Finance is a good option to go for.
I would suggest you to go for top collegs itself, like IIMA, B, C, L, K, JBIMS, Sydeham, etc.
Kindly check the list at below link:
https://www.shiksha.com/mba/ranking/top-mba-colleges-in-india/2-2-0-0-0

It depends on you. The minimum salary would be 10-12k, if you crack MT programme then you will get 25k or more than that. It also depends on your department for which you are interest.

You can do. But, you can also do Diploma in all four departments of hotel. If you want to make your career in any one department, then choose Diploma otherwise go for B.Sc in hospitality and hotel administration.

Go for MBA. Work hard in English and give IELTS or TOEFL. And, choose a good University.