Hi, @Hedvall, Lina ,
If the solution below not work well for you, please provide more information about your current setup. How do you set the flow, forms and list?
As you are using Power Automate to link the response to SharePoint list, I assume you use the Create Item action to add a new SharePoint list item with the information. I will not suggest using attachments. It is not quite convenient for future use. As you only want to have a connection between the item and the file, just add a new column called item location to store the URL of the file in OneDrive. We can create a hyperlink column, or a single text column to hold the URL. For hyperlink column, just fill in the link when you create the item. The only possible issue is that, if you want to use a description text, it will be needed to send a Http Request instead of filling the value directly.
If you want to add a description text while not willing to use a http request, using a single text column is also a choice. JSON formatting will help to convert the text to link.
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