Good to have you here, florence_tang.
The option to include a serial itemised running number in the Journal report is unavailable. You can only add columns for transaction NO. and QTY in the report.
You might want to enter the serial running number in the Memo/Description column. You can also export the report to Excel to come up with the data you need.
For more details about customising report, you can check out this article: https://community.intuit.com/articles/1775165.
I have articles here about managing reports in QuickBooks Online:
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