Please help with script

Good day!
Please help with writing sript on the shell.
There is a file in which only 1 field. It lists several hundred of some ID.
I need at that.
When on the field to collect a portion (10 to allow Ids separated by a comma) and after the formation of a portion cause allow any function, and a transfer portion (variable), etc. before the end of the file.
Many thanks in advance.

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