Woocommerce custom checkout and basket field

Hey,
I am trying to figure out how to create a custom field on the basket/checkout page that asks for a specific ID they were given. It would start with GCK and end with 3 numbers so the text field would have to conform to these rules.

Also, the code they input needs to match a code inputted in the backend to be validated, the same as the voucher system I presume.

Any help or plugin recommendations would be great.

Thanks!

https://wordpress.org/plugins/woocommerce/