Daily physical activity for 3 times a week is all i need?

Absolutely not: You need to be physically active 7 days a week with low to moderate intense daily activity. Sitting more than 6 hours a day increases risk for heart attacks by 50%. If you have a sitting job, get up every 15 to 30 minutes without touching arms or knees and do that 5 times or do some jumping jacks. Take steps, park farther away from destinations, look for chores to do, and keep moving all day long.

30 minutes: Current recommendations include 30 minutes of a moderate aerobic activity 5 times a week. If you prefer vigorous activity you can shorten the time to 2 or 3 times per week. That can be paired with 2 or more days a week of muscle-strengthening activities as well.