Hello everyone,
I am a manufacturer and want to start a new medical device manufacturing plant, but having poor knowledge of this field. So that's why I am looking for some expertise who help me with this.

Hire a professional.

Well, you will need FDA approval before you do anything, months or maybe years of in field study with people who might use this device, $$$$$ of Product Liability insurance etc. Are you sure the medical field is where you want to go-

"having poor knowledge of this field".

Here is one case with a very experienced well known company-https://www.drugwatch.com/2014/05/06/medtronic-settles-infuse-bone-graft-lawsuits/