You can save quotes with quote number prefixes. In order to do this, the setting Use prefix to manage quote types? must be configured under Orders / Quotes under the Sales tab in the Settings procedure. In that case the Quote type window appears when saving a new quote, where you can enter or select a prefix.
If you have chosen that prefix is mandatory in the above setting, default prefixes must have been registered in the Order Types / Prefix procedure.
The Quote type window.