I don't know where I found it but you need to downgrade one version of lazyMC from 2.11 to 2.10 I think, the newest version only supports 1.21+ mine works now after downgrading

it works perfectly fine now for me, here is the link to the releases page for the one that worked for me!
https://github.com/timvisee/lazymc/releases/tag/v0.2.10