No. The changes you make on the templates are not automatically updated on the content to prevent any unwanted changes on the content that is displayed on the screens.
This means that if you make changes on a template that is used on content, the changes are not updated on them, and no change on them will occur. If you want to display content that uses the modified template, you need to make new content using the template.
Note that if you want to keep the original template and create a similar one with changes, you can clone the template and then edit the clone.