One way to do this (which is the way I do it) is to have your tasks sync to a dedicated calendar on Google. I have several calendars (Business, personal, Financial, MLO) and I sync tasks to my MLO. When you complete an item in MLO, the task stays on the calendar. To limit/control the number of tasks that sync, I created a Zapier Zap that duplicates tasks on my main Google Calendar to my MLO Google calendar. That's the one I sync with MLO so I can see them. I usually work with calendar to Task list. If I go the other way, I manually copy the MLO calendar entry to the main Google calender but I don't have to do that frequently. Sometimes I'll create a time blocked calendar entry which gets synced and I can do several tasks on my task list as subtasks under it.
Works pretty well. I've created some custom views that allow me to see my daily events on my MLO daily task list along with the items I've identified I want to complete that day. It also allows me to add tasks that need to be completed prior to a calendar event like create an agenda or update slides for an upcoming meeting.
Hope this helps,
Leigh