*Reads. Looks. Cringes.*
There’s a couple of things here.
First item: I am running nginx (because all the cool kids are) and when I visit https://my-url-here/login/
I get 301 redirected to this URL https://my-url-here/wp-login.php
WordPress does that out of the box provide you have pretty permalinks correctly set up. I don’t know when that was added but it’s been that way for a while.
How have you configured your nginx to handle URLs?
The second thing is this: that’s not related to security in any way. The security is in the PHP code and renaming or relocating your login doesn’t really do anything. If you have strong passwords then the login attempts may be resource heavy but they’re not getting in.
If you really want to make your login more secure then consider adding two factor authentication.
I personally use this one https://www.ads-software.com/plugins/two-factor/ but there are others.