I haven't seen your previous posts so I may not have the logic right, but if I understand this correctly, you are trying to create a task, that starts today, but if today is a Weekend, have it start on the following Monday instead.
Then you want to have the task end date be one month from now. But again, if the end date is on a weekend, have it in on the following Monday instead.
So my approach would be:
1. Using your start with setting the variable to today's date. Don't need to as I could just use utcNow() in all my expression, but this works as well.

2. I am now going to take this TaskDate and now check to see if it is a Saturday or a Sunday. If it is a Saturday I will add 2 days (to make it Monday). Likewise, if it is a Sunday I will add 1 day to it to make it a Monday.
And I'll do this also for 1 month from now. These are long expressions and I could have done this in multiple steps, and if you want me to I can show you to help explain these, but this will work if you just want to cut/paste.

Expression in TaskStart compose statement:
if(equals(dayofWeek(variables('TaskDate')), 0),addDays(variables('TaskDate'), 1, 'yyyy-MM-dd'),if(equals(dayofWeek(variables('TaskDate')), 6),addDays(variables('TaskDate'), 2, 'yyyy-MM-dd'), variables('TaskDate')))
Expression in TaskEnd compose statement:
if(equals(dayofWeek(addToTime(variables('TaskDate'),1,'Month')), 0),addDays(addToTime(variables('TaskDate'),1,'Month'), 1, 'yyyy-MM-dd'),if(equals(dayofWeek(addToTime(variables('TaskDate'),1,'Month')), 6),addDays(addToTime(variables('TaskDate'),1,'Month'), 2, 'yyyy-MM-dd'), addToTime(variables('TaskDate'),1,'Month','yyyy-MM-dd')))
Now you can just use these dates in your Planner Tasks.
