Create Trigger in mysql

How can I write trigger for following

I have one customer table in that customer exist

if I <b>upload excel </b>file that contain customer name, employee name

<u>I have to insert this both in Table Employee Along Table</u> I.e

<b>Employee_Along_tb</b> which have two column Customer_id, Employee_Name

but uploaded file contain Customer Name I have to read customer id from customer name and insert into <b>Employee_Along_tb</b>