In order to create a Visit with Tasks, you need to define an Action Plan Template that creates the Tasks to associate with a specific Visit. 

Please see here for information on Salesforce's Action Plans: Enable Action Plans

1. Navigate to the App Launcher on the Salesforce Platform and select Action Plan Templates

2. Select New and give the Action Plan Template a:

  1. Name
  2. Description (optional)
  3. Target Object: scope to Visit
  4. Action Plan Type: scope to Visit Execution. 

Save your changes. 

3. Once the Action Plan Template has populated, select New Task

4. Fill in the Task Details and select Save

5. To add more Tasks, select New and then Task from the top of the screen. 

6. When you have completed your Task definitions, select Publish Template (see image for Step 5). Now you can connect an Action Plan Template with a Visit. Please see this article for more information: Create a Visit with an Action Plan