Railways exams

Hi there, Yes, you can surely prepare for all the competitive exams along with your graduation in fact this is the best time to secure your position in your dream job. I would like to recommend :
Daily go through THE HINDU paper especially the editorial part.

Hi,
Check your mail and SMS. You will get it there. Emails never get deleted. Please check there.

It's not necessary. It totally depends on the recruiters whether they take you or not.

Government exams and the IT certifications you mentioned are different things. Understand the fact that government exams are aptitude based. You will have to prepare Maths, English and reasoning.
If you are preparing for government exams and in your spare time you think of doing these certifications then go for it. But, if you think that your certifications will help you in exams then it's a wrong notion.
Yes, you can go for government exams till the time you are eligible for them.

It is must for any government. Job or government colleges.

Yes, distance education is valid for government jobs. For government jobs, selection process is same. So, no partiality is possible. Where only written exams are conducted, you can be rest assured that you are treated like any other regular degree candidates.

Yes, it's degree is valid, as it is a national University.