It's a pleasure to have you here, @steve 5. Let me clarify things for you about assigning initial equity.
In QuickBooks Self-Employed, the supplier's list is currently unavailable. Also, the available categories in QBSE are SA103F expense categories. For more insights, please refer to this article: About SA103F Categories.
I also recommend consulting your accountant to help you allocate the initial start-up for equity. This is to ensure that your book is balanced and accurate.
Otherwise, you can consider using QuickBooks Online. This version can set up equity accounts and suppliers. You can utilize this resource to help you move your QuickBooks Self-Employed data to QuickBooks Online: Switch from QBSE TO QBO.
In addition, let me share this link to help you categorise the transactions you download from your bank or enter into QuickBooks.
Let me know in the comment section if you have other questions about managing initial equity in QuickBooks. I'll be around to assist you again.