How to create System partition in Android? Which is accidentally deleted when tried to increase size.

Tools needed can be downloaded from forum.xda-developers Section 3.

parted_gdisk_fdisk_mkfs.ext4-AARCH64.zip - [Click for QR Code] (1.95 MB, 3326 views)
parted_gdisk_fdisk_mkfs.ext4-ARM.zip - [Click for QR Code] (1.56 MB, 4212 views)

In this case the phone is Mi Redmi 2 Prime (wt88047) and file used is parted_gdisk_fdisk_mkfs.ext4-ARM.zip

Unzip and push files to phone.

adb push PATH/TO/PARTED /

adb only available when phone is ON. Here no android OS in phone. So TWRP is used. For open in twrp first phone is started in fastboot by pressing low volume and power button together. Then phone is turned on to fastboot.
Then in command promt (adb drivers must be installed ) go to adb & fastboot path and do the command. TWRP must be downloaded keep in the same path of fastboot.exe

fastboot boot twrp-3.3.1-0-wt88047.img

Now adb is available.

Then take adb shell and using  parted create a system partition.

adb shell

chmod a+x parted 

./parted /dev/block/mmc0blk0 

unit b 

Print the existing partition table before you do any work on partition and save it as a picture.
The code below prints the partition table.

(parted) print free

Here you can 23 is missing. It is the accidentally deleted system partition

Its start and end Must be noted to Create the partition.

23 - starting block 236503040B - end block 1310244863B

mkpart primary ext4 236503040 1310244863 
name 23 system
quit

This is how a system partition is created for a android phone.