
Hi @Stephen Padayhag,
You will need to convert extension from .HTML to .aspx before upload the file to sharepoint. And you need to enable Custom Script by following powershell
Connect-PnPOnline -Url https://contoso.sharepoint.com/sites/StaticSite
$site = Get-PnPSite
Set-PnPSite -Identity $site.URL -NoScriptSite $false
Here is a nice article for upload html file steps. Please make a reference
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