If you're having a hard time viewing the video, try using HD format 720 on fullscreen mode.
Use the Rectangle Select tool, rounded corners set at 35 radius. Draw out the shape of the pill bottle. Save the selection to Path.
Change to the Paths dialog. Select the new path. Edit the points (nodes) like shown, below:
Select Path to Selection, change to the Blend tool. Bi-Linear for shape. Using a light blue/gray with white gradient, add the gradient path. Add a new transparent layer.
Click the Rectangle Select tool, no need for rounded corners this time. Add a selection for the bottle neck, save to Path, then using the Path tool, edit the nodes like shown:
Select Path to Selection. Switch to the Blend tool, using a darker grey color with white gradient.
Add a new transparent layer.
Using the Rectangle Select tool, make a selection for the bottle cap. Save to Path. Using the Path tool, edit the points (nodes) as shown below:
Select Path to Selection.
Switch to the Blend tool, and select Bi-linear as shape, and repeat to Triangular wave. Make a very short gradient path to get the "ridges" effect. Adjust the opacity to suit.
Make any adjustments or changes to the layers and selections, that you feel necessary.
Note: I rushed through these instructions due to a lack of time, and also would like to point out there are differences in the shape of the bottle neck and cap between these instructions and the video, in case it throws anyone off. But the steps remain the same. You are creating selections, saving them as a Path, editing the nodes (points), using gradients to fill, etc.