Hi,
that is too vague for anyone to offer meaningful help, so your responses are likely going to be limited.
This is a good read : How to ask a good question
as is this, where @meredydd explains to a user what is wrong with their question and how to make it better : How to access a drop down list from an ItemTemplate form
Remember most people here are just volunteers with day jobs, and will feel more inclined to help people who show they have done some research and testing, and clearly show what’s gone wrong. Your code snippet relies on others to try and guess what else you’ve done.
Please don’t take offence to what I’ve written, but if you read the links I pasted above and follow the advice, you’ll find people on here very helpful.