Eligible for lump sum gst???

Dear sir,

I have plan to start three different business 

1) Mineral water bottle

2) gram flour distributorship

3) home furnishing

Above business supply in local area

Since above three r from different category, my question are

1) only one gst number is required?? Or have to take three gst number for different business???

2) if my total turnover for above three business is less than 75 lakh annually ???? Am I eligible for lump sum GST???

Thanks in advance for your valuable advice