Hi @Aleksandra Dondziak,
Per my knowledge, there is no way we can save a site as a template and use it in the organization. The template created can only be used when creating a sub-site.
Are you saving a SharePoint site as a template and want to create a new subsite from that template?
If so, here are the steps:
- Please contact your Global Administrator or SharePoint Administrator to confirm that the Save Site as Template option is turned on.
2.Log in as a site administrator to the site you want to set as a template. Navigate to Site Content > Site Settings > Site Actions > Save site as template.
3.Fill in the template information and click OK when you are done.
4.This is optional. If you want to create your website with this site template in another site collection. You need to download this template and upload it to other site collection.
5.You will be able to see your templates in "Custom" when you create a sub-site.
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