Sometimes things that are easy to explain in English are hard to implement in the constraints of Airtable. It sounds like you are trying to create a first-in-first-out system.
Two approaches come to my mind
I would do this with a scripting automation. When a record is marked as used, have a script search for the oldest unused record and mark it. This method requires having someone with the ability to write a script.
Another option is to use a control table with a single control record. All new records are linked to this control record and a series of back and forth rollups identifies the oldest record. When a record becomes used, it unlinks itself from the control record. Normally I don’t like this method if there could get thousands of linked records, but if the queue stays at a manageable level and you have enough automation runs to support the system, it is a no-code method that works.
So for a View to only show the eldest record that’s not used, I’ll suggest adding one extra tick field called “Eldest Record”, and an Automation checks all records, and ticks the eldest record that meets the criteria.