There are two types of Autoplay in Netflix, the Back to back episode autoplay and the trailer preview on icon during navigation.
Back to back episode autoplay can be turned off in the setting in the website section of Netflix. The option is not available on the app. In the website version, locate the Account page link from the drop-down menu, where you will find the Profile & Parental Controls. There you can change the episode autoplay setting in the Playback Setting. Don’t forget to press “Save” after checking or unchecking the box of Autoplay next episode in a series on all devices.
The trailer preview in the icons of the navigation page is switched off similarly. In the website version, locate the Account page link from the drop-down menu, where you will find the Profile & Parental Controls. There you can change the episode autoplay setting in the Playback Setting. Don’t forget to press “Save” after checking or unchecking the box of Autoplay previews while browsing on all devices.