Hi @Garant,
Customizing the submission process, while possible (has to be done by modifying the code), can have some troublesome implications for OJS: How to customize submission form? - #3 by t4x0n
As this post points out, Modify or add submission page using a plugin in OJS 3.3.0 - #16 by Justin_Laurenso - there is a third-party plugin that can help you avoid the customization process and add additional metadata fields: GitHub - TIBHannover/optimetaCitations: OPTIMETA OJS Plugin - Citations Plugin - I haven’t used it before, so can’t speak to it directly, but it might be worth exploring.
In terms of exporting information like a spreadsheet, there is the Articles report in the reporting function of OJS that does this, to an extent - that might also be worth looking at, to see if meets your needs.
Best regards,
-Roger
PKP Team