Light distance from Seedlings

Hey guys,
I'm growing LA Confidential in a 5x5 in coco coir/perlite, starting out in Jiffy pellets. I have the HLG 650r LED light:
https://horticulturelightinggroup.com/products/hlg-650r
Keep in mind I don't plan on getting a second light for seedlings, at least for my first grow. I will only be using this light.

When I place my seedlings under light for the first time, how high should I place this light above them? How low should I dim?

Any help is greatly appreciated.

Distance where the light is touching the seedlings should help, i typically had done it with 1m or 1.2m away, and its worked pretty fine, recently i dropped that to 80cm the top of the seedlings to the light

Its very important to feed gently and often at the beginning of its life. I feed every 2 days when new seedlings havr been germinated in the soil.