Does the health function of iphone6 need to be connected to the Internet?

It depends on which function you use. Some need networking, and some just need to connect auxiliary devices, such as pedometers and bracelets.

Click the health data item at the bottom of the interface, and then click the fitness number classification to see the recordable items.

When you click on a record item to enter, you can see the chart data information automatically recorded by the iPhone5S device. If you want to display it in the chart summary interface when the software starts by default, just turn on the "Display in Chart Summary" switch below.