Dear Kaelie,
To create a custom site template, you may use the site script in JSON. You can use Power Automate or PowerShell to apply it.
Here is an example to apply the example script in Get started creating SharePoint site templates and site scripts | Microsoft Learn to the site in our environment with Power Automate.
I name this template as sitetemplate1 in Power Automate.
![Image](https://filestore.community.support.microsoft.com/api/images/3beb3c98-4e43-4ad1-83b1-d701e09ec389?upload=true&fud_access=wJJIheezUklbAN2ppeDns8cDNpYs3nCYjgitr%2BfFBh2dqlqMuW7np3F6Utp%2FKMltnRRYFtVjOMO5tpbpW9UyRAwvLeec5emAPixgq9ta07Dgnp2aq5eJbnfd%2FU3qhn54KmMaR3K%2B1%2B1g%2FFrq359qOV9XeaIjk5ITORR9lvYS%2BDMsslfK7flPhbuiIldObVZF9eoakAyfSNXWQ0gezrwwYzZRJ6zWYngVeIhhHVctTLtf6XBqiRLbh%2FwSWkinKHFlanPiswv1FdgbrHV041mn0%2FAVorV2MIk%2BjSVQJ8NUOJDjDOcpqpI1H4qniwZ%2FTNmLR1WM5Zf1UOH13QqcLoxH8a7frjHzPV%2Ftp3UxihFFjXgW%2FsftXYqTcZ%2Bxa8F%2B2DziC9cVQD93XYCy42hui9G75Ow9xPNdO8Zy%2B9JUlsrEGCA%3D)
![Image](https://filestore.community.support.microsoft.com/api/images/c3a6913d-8711-4050-871e-0f05bbd6a3ac?upload=true&fud_access=wJJIheezUklbAN2ppeDns8cDNpYs3nCYjgitr%2BfFBh2dqlqMuW7np3F6Utp%2FKMltnRRYFtVjOMO5tpbpW9UyRAwvLeec5emAPixgq9ta07Dgnp2aq5eJbnfd%2FU3qhn54KmMaR3K%2B1%2B1g%2FFrq359qOV9XeaIjk5ITORR9lvYS%2BDMsslfK7flPhbuiIldObVZF9eoakAyfSNXWQ0gezrwwYzZRJ6zWYngVeIhhHVctTLvKpBHRFhdDPydKBMEw7n0sCVDM84t36DKpQIjMiOGG3pZcEDOJh8a9BL7v9cHW0qHMjfflMiWuF6Kja5JRzWDrR2inN36mW7%2FlHMg4lil3u6sLPD58fAAvyHo3%2BMas6ALqay%2FePSRMxgDNPQvKq2fbqLKuD32UxdSwORrA8UWkKR3CuHVlX5spD7lwxoLyzRk%3D)
![Image](https://filestore.community.support.microsoft.com/api/images/6fdd01e2-d7e4-4fb0-8255-f30532040647?upload=true&fud_access=wJJIheezUklbAN2ppeDns8cDNpYs3nCYjgitr%2BfFBh2dqlqMuW7np3F6Utp%2FKMltnRRYFtVjOMO5tpbpW9UyRAwvLeec5emAPixgq9ta07Dgnp2aq5eJbnfd%2FU3qhn54KmMaR3K%2B1%2B1g%2FFrq359qOV9XeaIjk5ITORR9lvYS%2BDMsslfK7flPhbuiIldObVZF9eoakAyfSNXWQ0gezrwwYzZRJ6zWYngVeIhhHVctTLsWBB77P0Az2LLMfL%2BDPgn2cMbo93nuXb5rf9Paieve4JC00FXzGiLISS6vUxYguAgAcoc4%2BKUeZlGj3pEzXFkc1etQ4v2dOZ1Q04%2FWwjJqW1BwnjOjp65cwI6e1PXFBR0lx%2Bb37u5Cm49Add9rJYoYpAEECNuJhzWsTpmF%2FDAwkrlba8MNcpFiVPN2wNhsoXE%3D)
![](https://filestore.community.support.microsoft.com/api/images/85355902-41c9-437e-af5c-74e9a080cf00?upload=true&fud_access=wJJIheezUklbAN2ppeDns8cDNpYs3nCYjgitr%2BfFBh2dqlqMuW7np3F6Utp%2FKMltnRRYFtVjOMO5tpbpW9UyRAwvLeec5emAPixgq9ta07Dgnp2aq5eJbnfd%2FU3qhn54KmMaR3K%2B1%2B1g%2FFrq359qOV9XeaIjk5ITORR9lvYS%2BDMsslfK7flPhbuiIldObVZF9eoakAyfSNXWQ0gezrwwYzZRJ6zWYngVeIhhHVctTLtqik8A0aQ5Bi2gTQHWcykiWlVr759gyumvANEc7w6BAeI5AWXcbBXkYnzCCun6UowrnIYNeRoUf4j5K04X4n01k78T4SRGAIN9emQdElGI%2FLHzA0OQObRkNYI5KVk4SZv5f77zQXIZlAP1kAxP6VDSeo5%2Bj36L5fz39h60TEqdbpBFY2zXcGRT90Vsdy%2FKuAo%3D)
.
Create the site script.
Method: POST
Uri: /_api/Microsoft.SharePoint.Utilities.WebTemplateExtensions.SiteScriptUtility.CreateSiteScript(Title='sitetemplate1')
Headers:
{
"Content-Type\n": "application/json;charset=utf-8",
"accept": "application/json;odata.metadata=minimal",
"odata-version": "4.0"
}
Initialize variable 2: outputs('Send_an_HTTP_request_to_SharePoint')?['body']?['Id']
Add the site template to the site.
Method: POST
Uri: /_api/Microsoft.SharePoint.Utilities.WebTemplateExtensions.SiteScriptUtility.CreateSiteDesign
Headers:
{
"Content-Type\n": "application/json;charset=utf-8",
"accept": "application/json;odata.metadata=minimal",
"odata-version": "4.0"
}
Body:
{ "info": { "Title": "sitetemplate1", "Description": "sitetemplate1", "SiteScriptIds": ["@{variables('ScriptID')}"], "WebTemplate": "64" } }
Result:
![](https://filestore.community.support.microsoft.com/api/images/55a2074a-aac6-44d7-9668-cb6946782f5a?upload=true&fud_access=wJJIheezUklbAN2ppeDns8cDNpYs3nCYjgitr%2BfFBh2dqlqMuW7np3F6Utp%2FKMltnRRYFtVjOMO5tpbpW9UyRAwvLeec5emAPixgq9ta07Dgnp2aq5eJbnfd%2FU3qhn54KmMaR3K%2B1%2B1g%2FFrq359qOV9XeaIjk5ITORR9lvYS%2BDMsslfK7flPhbuiIldObVZF9eoakAyfSNXWQ0gezrwwYzZRJ6zWYngVeIhhHVctTLvfe0lDYwL4%2BDYxDkIGDmbCYZRTME%2FjuX25jZq%2BJLKjQZU0WfZ2ZwQyCeYtKTWrOJOqiZ0sUD00s2WfFs6XKWIwJ6%2BiAp%2FbMq5mn%2B3mfOSFhUywqs8Wumrm3%2B7K%2BiRSUaKvZX3GT7T0NASRZQC0Ch0IePxYTtyxDlvdUjzBZEtwROK3oIM8TuNmjTOgj1hFthQ%3D)
.
You can also use PowerShell to create and add it by the steps in Get started creating SharePoint site templates and site scripts | Microsoft Learn.
Thank you for your effort and time.
Sincerely
Cliff | Microsoft Community Moderator