How can I create a new HR department

Good Evening to everyone.
Recently, my company (almost 200 people) has decided to create a new HR department. I will be responsible of this action and I need your support. How can I start with that beacuse it looks like chaotic? Could you give me any advice? Could you give me any guideline?
Thank you in advance!

What is the existing set up for managing people?
What is your qualifications from HR angle?
Setting up HR means a lot of records have to be created.
Starting from record of employees-name, date of joining, age, pay scale etc.
Legal compliances aper the laws of the nation/state where your company is set up.
What looks chaotic now will get resolved.
Take the first step of data organisation of all employees.
Then see what all is required to set up their payroll system by proper automation.
Then move on step by step.
Give additional details,for other members to comment