Multiple subtasks and check lists creations in modern SharePoint list

Currently I am managing my project tasks through SharePoint lists with power automate. I have couple questions;

1. How to create multiple subtasks for a single task item?

2. For each subtasks we have to use various check lists. And these check lists are based on the type of subtasks. So the check lists need to be filled and attached to the subtasks before submitting the subtasks for review and approval. How this can be possible?