Where can you find Enterprise Manager (EM) Database Control URL / Link.  In-order to open Oracle EM you need the correct URL.

You can find the correct link by opening the read-me file in the oracle home folder

For example: ORACLE_HOME/install/readme.txt

Just search readme.txt file in the folder where oracle is installed or browse manually to the folder where oracle is installed. For example, I installed oracle in C:/app/Anish(your computer name)/product/11.2.0/dbhome_1/install/readme.txt

When you open the readme file you will find the correct link. Check the below screenshot

Oracle em

Thanks for reading.