The easiest way you can follow is;
1. Install the Jetpack plugin for instance; https://wordpress.org/plugins/jetpack/
2. Go to Dashboard>>Jetpack>>Settings and activate Jetpack Widget Visibility module
3. Now go to Appearance>>Widgets and addthe desired widgets/contents in your Bottom widget area. You can find a visibility tab below your widget. Click and select Show if: Page is Post Type:(posts) or your desired location.
4. and then save it
Please follow the steps and let us know.