Follow these steps to upload your theme in Drupal:
STEP 1: Log in to your administrator Dashboard in Drupal.
STEP 2: From the to menu of dashboard, navigate to Appearance and Click on Install new theme option.
STEP 3: As you click Install new theme, you will see a browse window as shown below. Browse your theme and click the “Install Now” button.
STEP 4: After the successful installation of your theme , a confirmation message will display as follows. Now Enable the theme by selecting your theme from Enable newly added themes.
STEP 5: After enabling the theme, it’s all done and you may visit the site to see how it looks on browser.