Nre / nro / transfer money

Hello

Will go to Zambia for Work in last week of Sep  2018

I would be spending less than 182 days in india and have never left india in last 4 years even for a day.

There will be no earnings like rent, divident  in my name in India nor do i have any investment in todays date

i would
be in Zambia for 2 years.

Salary in Zambia will be paid in Cash

What i need help in understanding is -

1>> I want to send some money to Parents in India to meet their household / medical
expenses 

I plan to open a account in Zambia and from that account transfer money to parents account

2>> I dont want to  keep a lot of money in Zambia either in cash with me or in
Zambia bank account

Should i transfer out my monthly left over money to my Indian account, if yes should it be NRE or NRO 

i want to minimize or eliminate tax as much as possbile and be compliant with IT laws

3>> Should i close my savings account in india or just convert
them to another type

4.>> Need i open a NRE account in India right now

Thanks