Please check the below article for more details on creating Manual Test Cases and adding Steps to it:

How to add/edit/delete Test Steps for manual Test Cases?

Once the Test Case is created, we can create an Execution for that. Please check this article for more details on creating an Execution:
How to create/edit/delete Executions?

Now, you may start the Execution from the Executions page.

Now that the Execution has been started, let us see how we can manually update the status of Executions for manual Executions once the process is complete.

1. Click on View Reports from Executions page.

2. In the Run Results page, click on Run ID which you want to update.

3. Click on Test Case Results. You will be taken to the Test Step Results page as shown below:

4. Click on the Update button on top right corner to update the 'Test Case Results' as shown below:

Set the Start Time, End Time, Status, Message and upload attachments, if any, before clicking on Update. The status of the Test Case Result will be changed as per your updation as shown below. However, the Test Step status has not changed yet. Let us update that now.

5. Click on the Update button on each of the Test Steps and update the Test Step Result as follows:

6. Repeat the same procedure to update the status for Test Suite, Test Environment and Run ID.

That's all we need to do in order to update the Run Results for Manual Test Cases.