Diploma

You can opt for a job if not then you can do B.Sc in electronics. There are few colleges which offer lateral entry in B.Sc electronics, but you can try your luck.

No, you cannot pursue ITI and engineering simultaneously. Even if it is possible then no one can study two subjects at the same time.

You can pursue B.Sc in computer science.

Hello Sanjay,
Frankly, I have not understood your query. You are already doing a job for three years after the completion of Diploma.
You have to decide about your future. You can take a break from the job and go for graduation in fire &safety. You can continue in the same job. But, what's your passion? I would advise you to follow your passion.