Hello Barb

You can do this using set defaults feature in odoo

Start this by activating the debug mode 

after that create a new task

Write the template you want in the description

after that press on the debug icon and press on the set defaults 

after that select the description as the default value

and dont select a condition unless you want one and set it to all users or to yourself only

it should look like this

If this helps, please upvote my answer and mark it as correct