How to enter exercise minutes manually into iPhone 6 plus health app?

Hi lalipatti,
Thanks for using the Apple Support Communities. If you are looking to manually add exercise data to the Health app, you should be able to do so under the Activity data type, either by selecting the specific data set (like Cycling Distance), or by scrolling to the bottom and selecting Workouts. Look for any of the entries that have a "+" in the upper right hand corner, as noted here:

View and manage a data type. Tap Health Data, then tap the data type. For example, tap Activity, then tap Steps.

• View your progress over time: Tap the D (day), W (week), M (month), or Y (year) tab.

• Move a data type to the top of the Today screen: Turn on Add to Favorites.

• Manually enter data: Tap in the top-right corner of the screen.

• Delete data: Tap Show All Data, swipe left on a data record, then tap Delete. To delete all data, tap Edit, then tap Delete All.

• View apps and devices allowed to share data: Tap Data Sources & Access.

Get started - iPhone User Guide
Regards.