How to insert users in a dropdown based on their designation in php from database data


In my project there will be some users with respective designations how can i create a dropdown with only specifc desgniated users to assign them tasks.

In Detaill:
I will create an order / task, after i goto all orders, there the orders will appear in a table, in that table last column have a check box to selct the order and then i need a dropdown option with list of users whos designation is CSR/CRM to assign the orders/tasks to them.

Please helpmwith this, send me a sample table data with this functionality