Need help on making a loop script base on what is inside a file...

File to read: List.txt
List.txt contains below w/c are file name as well:

SAMPLEa
SAMPLEb
SAMPLEc
SAMPLEd
SAMPLEe
SAMPLEf
.
.
.

Want to make a loop that will manipulate those that are inside the file.txt w/c are also filenames.. For example, chmod those files…

Thanks in advance for the help...