firstly open the terminal. If you have mongo credentials then write the below command.
mongo -u admin
Note:- where admin is a username
If you did not create credentials then you can directly login write the command
Now, create the database through below command
> use employee_management
> switched to db employee_management
if you want to see all databases then write the below command.
> show dbs
Note:- it will show all databases which has collection.