A star note is a replacement bill for a bill damaged during printing at the mint. They have to designate the replacement notes (usually a full sheet) with a star at the end of the serial number. The original sheet of damaged notes are then incinerated or most likely shredded into dust.
The OP is just asking a vague question that has nine different variables in the answer. The premium collectors place on start notes depends on several variables just like most hobbies.
I have sold many 'star' notes on ebay over the years and used to have a reliable source for these replacement bills until Covid killed the senior center flea market world.
