Hello,

If you complete diploma course in fire safety management then you can get jobs in various manufacturing plants and factories but your salary will be less as a fresher as you will earn around 10 to 12,000 per month may be a little more than that. This is not a very suitable career choice because later on your will have very less option of growth. So, you must choose a proper path for a solid career. I would suggest you to complete your 11th and 12th and then go for a long term goal in bachelor either in engineering architecture or any course in which you are interested so that you can have a wide range of options and a fulfilling career.
Considering you passed 12th with science, i would personally suggest you to go for engineering course. B.tech courses is of four years duration and after completing B.Tech you will have many options.

I hope this helps.