CBSE 10th

To pursue graduation, you need to complete 10+2 and 10th first. If you have completed your secondary (10th) and Higher Secondary (10+2) then you can enroll for a graduation course in any university as per their eligibility criteria. In case you have not completed 10th board itself (as you mentioned), then firstly you should complete your 10th board followed by 12th and then apply for admission in graduation.

Class 10th from NIOS is equivalent to a degree from any other secondary board like CBSE, NCERT, State Board. So You can apply basis on NIOS degree considering you should meet other required minimal criteria for admission in Hotel Management.

In class 10th, if you have more than 50% marks in English you are eligible. And in class 12th, you will have to score more than 60% then only you will be eligible for the course. And if not more than 60% you can join GP rating courses too.

Considering your academic records and work experience, you have good chances to get into IITs for MBA/PGDM. You must apply. All the Best!