Q: How Do I Set Myself To Be The Default Account To Login When Turning On My Laptop?

       https://support.apple.com/kb/PH18901?locale=en_US

I realize this doesn't answer your question, but it does answer the question in your title, so It might be helpful to anyone searching.

If you go into system preferences and select "users and groups"

at the bottom of the left hand side of the window there is a little house icon that says "Login Options" select that.

If everything is grayed out then you must unlock the padlock in the lower right lefthand corner.

Now you can choose your user name from the dropdown menu named "Automatic Login:"

See the Apple KB article below. If you cannot turn this on you may have FileVault enabled. If so you must disable disk level encryption.

Best,

Grahas

Set your Mac to automatically log in during startup - Apple Support