In Mailchimp:
This is all archived campaigns.
Folder - Newsletter Archive, Folder Archive Code, copy code. Here in Wix: Add code.
More detail here.
Mailchimp:
Send the campaign. Create a folder with name for this newsletter (month year). Move campaign to this folder. Under Campaigns, go to Folder just named above, Folder Archive Code, copy code.
In Wix:
Add More, HTML, paste code.
Take screenshot.
Bottom left icon on screen, search for snipping tool. Save the image as nl monthyr.
Link screenshot to URL. To get URL, select newsletter, under View Report drop-down menu, View Email, copy URL.