In order to change the position of module, please read below steps.

1. Go to Back-office > Design > Positions:

On the position page you will find the list of module in each hooks.

module-position

2. Now, Just drag and drop or use up and down arrows to change position within a hook. Changes will be saved automatically.

change-module-position

In the below screenshot, You can see that position of Image Slider module has been changed.

changed-module-postion

3. Let’s see the front-office view.

module-position-front-office

I hope this was helpful for you!