Buy all the stocks in an index at the same time

Hello all.
I request experienced investors/traders here to shed some light on this.
I plan to run a strategy on Micro Cap 250 index, which will require me to buy all the 250 scripts in that index at 3.29 pm
It will not be possible for me to enter buy orders for 250 items manually.
The basket feature on Kite will also not be useful, as it will require me too execute 13 baskets
Is there any other way for me to execute this using any tools that are available for retail traders?
My requirement is that I should only have to enter allocation per script (which is equal for all the 250 items) and press a single buy order which will execute 250 separate orders at 3.29 pm
Do let me know, if you guys have any idea which might help me with this.
Thank you.