I have a problem and I want to explain this with an example, if anyone could help me, I would be very glad

There is a A activity, this activity starts at 1 february and finish 1 april according to schedule and duration is 60 days ( 1 april - 1 february = 60 days). This Activity's deadline is 30 april and it doesn't have to finish later than 30 april

Anyway if everything ok it would be start 1 february and finish 1 april and it needn't any change in dates ( I mean earlier than 30 april ) like this circumstance

 For example this activity did not start 1 february, started 15 march and if it was scheduled (F9) at 15 march. The programme added 60 days on start date (15 march) and finished 15 may (15 march + 60 days = 15 may ).  I want definitely that this activity could not pass deadline (30 april) and it would start 15 march and finish 30 april (deadline)

  Also resource name of this activity is x, the quantity of x equal 180 unit, at first circumstance activity original duration would be 60 days and 3 unit (180/60 = 3) was spent as per day and when I printed resource report I saw that 90 unit was spent on february and 90 unit was spent on march

 But at new circumstance activity started on 15 march and finished on 30 april because of deadline and it takes 45 days to finish and 4 unit (180/45 = 4) was spent as per day when I printed resource report I saw that 60 (15*4=60) unit was spent on february and 120 (30*4=120) unit was spent on march

So I want it to be like underline paragraphes , Howcan I do it like underline paragraphes? Which constraints can I use ?