Sorry @Nirav_Chaudhari , this dropped off my radar.
I didn't get time to write the blog but here is the idea.
SharePoint
1) Create four status columns Manager1 Status, Manager2 Status, etc to save the responses from each manager
Power Apps
2) Create a Power Apps form that has an Approve / Reject option. Add logic so that the buttons should only be visible to the assignee.
3) Update the choice column based on the button clicked using a Patch function
4) If the all the Status columns have the value approved, you can mark the request as Approved.
Power Automate
The flow will not have any approval actions. It will only send email notification with a deep link to the Power Apps form
I will blog this, some day, maybe sooner