On the Medical expense section do I have to include the amt on T4 or is it automatically added to the other expenses for calculations?

Yes, the amount in box 85 on your T4 indicates the premiums for private medical plans that you paid through payroll deductions and they will automatically be entered on the medical expenses worksheet for you. 

does that count in the minimal amount to have to claim other medical expense receipts ?

Yes it is part of the total medical expenses and will be used to determine if your minimum (threshold of 3% of your net income) has been reached.