A template is a note you reuse, such as a meeting agenda, a weekly review, or a bug report. Templates are normal notes kept in the vault's templates folder.
Make one. Write the note the way you want it, then choose Save as template from the note's ⋯ menu or the Tools menu.
Start a new note from it. Choose Tools → New note from template…, or use the command palette or a folder's menu, and pick the template.
Or insert it. In a note you're already writing, choose Tools → Insert template to add the template's text at the cursor.
Change which folder holds templates in Vault settings → Templates folder.
Name a template Daily and every new daily note starts from it.