How to connect from windows command prompt to mysql command line

C:\Program Files\MySQL\MySQL Server 5.7\bin> mysql -u username -p

Then it will ask for the password. Enter the password you set for the username during installation while adding db Users.

Use this :

mysql -u user_name -p  then press_enter_key

then type password

i.e.

line-1 : mysql -u root -p

line-2 : admin

The cd in your question is invalid (quoting it here because you've removed it once, and it was there when this answer was posted):

cd CD:\MYSQL\bin\

You can't cd to CD:\ anything, because CD:\ isn't a valid directory in Windows. CD: would indicate a drive, except that drives are restricted to a single letter between A and Z.

If your \MYSQL\BIN is on drive C:, then your commands need to be:

C:\>cd \MYSQL\Bin
C:\MYSQL\Bin>mysql -u root -p admin

If you're not already on C: (which you'll know by looking at the prompt in the cmd window), or your MySQL folder is on another drive (for instance, D:), change to that drive too:

C:\> cd /d D:\MYSQL\Bin
D:\MYSQL\Bin>mysql -u root -p admin

The .exe after mysql is optional, since .exe is an executable extension on Windows. If you type mysql, Windows will automatically look for an executable file with that name and run it if it finds it.

Note that in both my examples of running mysql, there are no = signs. You should just use -p with no password, and wait to be prompted for it instead.