Advice on which widget is appropriate

I am creating a task list and require the form user to tick when each task has been completed and then clicking on the submit button. Which widget would be appropriate?

I assume that you want your users to select multiple tasks. I may suggest using Checklist widget to achieve that. See the gif below:

Please check the link for further details of  Checklist Widget:

https://widgets.jotform.com/widget/checklist 

If you want your users to add more responses questions- in your case tasks that they have completed- I may suggest using Dynamic Textbox widget. See the gif below:

Please check the link for further details:

https://widgets.jotform.com/widget/dynamic_textbox 

If you have any questions, please let us know.

Great thanks