Missing member module error

I am currently running EE 4.1.2 on my localhost as I develop a website. I began with Core and after a few days purchased an EE 4 licence, which is installed and running on the same site. I didn’t manually upgrade anything; I just used the one-click updater to move up to the licensed version.

Today I started to build a section of the site based on the Login Form Tag https://docs.expressionengine.com/latest/member/index.html#login-form-tag and upon loading the page, I get an error:

Error

The following tag cannot be processed:

{exp:member:login_form}

Please check that the ‘member’ module is installed and that ‘login_form’ is an available method of the module

–

Having read through the docs, I noticed that this module is not managed in the control panel so it doesn’t show up in that spot. I also see in my system/ee/EllisLab/Addons directory that “member” is there with all of its files (e.g. addon.setup.php, etc.)

So, what am I doing wrong? How do I install this ‘member’ module like the error is telling me to do? Am I still stuck on Core without knowing it?

Thanks for any help,

Geof