MySQL split first and second element from one column to different colmns

I have three columns in my DataBase

ID | boundary_coord                          | lat | lng |
------------------------------------------------------------
1  | [[27.913308738086336,78.0780080756358], |     |     |
   | [21.913355835273993,75.07837828047921], |     |     |
   | [26.91360564733089,32.07834574752177],  |     |     |
   | [23.9136475694797,35.07799837107608],   |     |     |
   | [34.913308738086336,34.0780080756358]]  |     |     |
2  | [[16.966884703254756,79.30961584505829],|     |     |
   | [17.967035001856917,73.30904577055392], |     |     |
   | [13.967680163832473,74.30925753680006], |     |     |
   | [15.967591705852122,71.30952320375857], |     |     |
   | [12.96751655678886,77.30982165205582],  |     |     |
   | [14.966884703254756,72.30961584505829]] |     |     |

Now I am trying the get first value from the boundary_coord put it in the lat column and get the second value from boundary_coord, put it the lng column

So in Mysql I wrote this

SELECT SUBSTRING_INDEX(boundary_coord,',',2) AS LAT_LNG, farm_name FROM `farm_management_farm` WHERE boundary_coord is NOT Null

OUTPUT

LAT_LNG
-------------------------------------------
[[27.913308738086336,78.0780080756358]
[[16.966884703254756,79.30961584505829]

Clearly, this is not the output I am expecting and one more prob that is in the starting I am getting two openings [[

Expected output

ID | boundary_coord                          | lat              | lng            |
-----------------------------------------------------------------------------------
1  | [[27.913308738086336,78.0780080756358], |27.913308738086336|78.0780080756358 |
   | [21.913355835273993,75.07837828047921], |                  |                 |
   | [26.91360564733089,32.07834574752177],  |                  |                 |
   | [23.9136475694797,35.07799837107608],   |                  |                 |
   | [23.9136475694797,35.07799837107608]]   |                  |                 |
2  | [[16.966884703254756,79.30961584505829],|16.966884703254756|79.30961584505829|
   | [17.967035001856917,73.30904577055392], |                  |                 |
   | [13.967680163832473,74.30925753680006], |                  |                 |
   | [15.967591705852122,71.30952320375857], |                  |                 |
   | [14.966884703254756,72.30961584505829], |                  |                 |
   | [14.966884703254756,72.30961584505829]] |                  |                 |

You can use JSON_EXTRACT to parse the array you have in boundary_coord like so:

SELECT id, boundary_coord,
JSON_EXTRACT(boundary_coord, '$[0][0]') AS lat,
JSON_EXTRACT(boundary_coord, '$[0][1]') AS lng
FROM `farm_management_farm` WHERE boundary_coord IS NOT NULL;