Follow the steps, as stated below:
1. For horizontal layout, hover your mouse next to the three vertical dots. You’ll see the Edit button. Click it to open the dialog box.
2. In the dialog box, you can make changes to the name, contact, address, organization, label, owner, sub-owner, and visibility.
Hover your mouse next to the three vertical dots.
3. To delete the contact, click on the three vertical dots at the end of the row and select the Delete button.
4. To copy, select the Copy button and fill in the fields in the dialog box.
5. Alternatively, you can tick the checkbox next to the contact's column. An action bar will appear where you can select the icon to do the respective actions such as; change the owner, change the label, visibility, delete, copy, export or make any necessary adjustments.
6. For the card view layout, tick the checkbox on the top right of each card and click on the icon at the action bar for the changes you would like to make.
Whenever you copy the contacts, a warning message will pop-up stating that there will be duplicated contacts if you saved. You may proceed as there are no restrictions for repeated contacts.
Read on the following article on What is on a Contact page? to know more!