Will it be Okay If i don't give noc at my Dv and don't tell employer about my current job?

I joined rrb bank and just attended 2days training and 3rd day reported to allotted regional office(400 km away). Took leave without pay 2days due to Interview for another job. Then I couldn't go back there due to family problems. I intimated them of 10days leave through an employee at head office. After four days, I got another job in central govt with better pay. As I had document verification there , so I thought after dv, I will go and resign and serve notice period. 3 days after this hrms at my ro , removed me from whatsapp group. Then I called them, they told me to mail, I wanted to go and join the job, but my parents denied. They told me to 1st go for dv, as I might not get leave if I join. so I mailed them and asked for another 1month leave. I didn't even recieve salary for this month , Now I am in extreme stress if I tell them or not about the selection and Will they give me noc? Or what if I don't tell my employment status at dv. I have not mentioned about it in my application as I got job months after it. And it is written there central govt employees have to bring Nov as mentioned in their application form. will I have to serve notice period if I resign or will they let me go without it as I haven't worked. I am afraid if I told them of selection and they write something wrong about me to my future employer. Please tell what to do.