You can import tasks from Todoist by clicking the "Import tasks" button on the top of your tasks or by right clicking on a task and selecting the "Import tasks" option.
Select then "Todoist" in the list of import options and enter your Personal Access Token from Todoist and click "Connect to Monday.com".
If your tasks contain Team members, it will be asked to you to match them to existing team members, create new ones or ignore them.
Once done, just select the destination of your import and finish your import.
How to get your Personal Access Token in Todoist
Inside of Todoist, access your settings (wheel icon on the top right) and go to the "Integrations" section.
You'll find your token in the "API Token" section on the bottom.
Copy your token and paste it in Planless.