How to add Single Post Template in Wordpress

Single Post Template adds the ability for your theme to include "Post Templates" in much the same way you can add "Page Templates" …

Noted That:

To install correctly this single-post-template.zip.
Fisrt Download the single-post-template.zip to your computer
Extract/Open single-post-template.zip to Your Computer.
Then, Find readme.txt file inside single-post-template.zip and Open readme.txt.
Now, Read the Requirements of this plugin. Which Wordpress Version and PHP Version are required to run this Plugin in Your Wordpress Site.
Then, Follow the Tips Below.

Start the Tips:

1. First Download "single-post-template.zip" Plugin to your Local Computer. (Click Download)

2. Then, Login to your "yourdomain.com/wp-admin" Dashboard.

3. Then, Click on "Plugins" + "Add New" from left sidemenu of Dashboard.

4. Now, Click on "Upload Plugin" button.

5. Now, Browse "single-post-template.zip" Downloaded plugin from your computer, Where you downloaded single-post-template.zip According to Step – 1 Above then, click on "Install Now"

6. Now, Click on "Active Plugin"

7. Then, See left sidemenu. "Single Post Template" folder is added on left sidemenu. Now, Click on "Single Post Template" folder.

Noted that: If you do not see "Single Post Template" folder on left sidemenu then, see at left sidemenu "Settings" or "Tools".

8. Now you configure yourself oR Watch video tutorial below about Single Post Template Configurtions and Settings or How to work "Single Post Template" in your WordPress site.

After Activated Plugin According to Step-6 then,

Go to "Plugins" + "Installed Plugin" from Wordpress Admin Panel Leftside Menu.
or Direct go to: https://yourdomain/wp-admin/plugins.php
Then, Find "Single Post Template" Activated Plugin from Plugin List.
Then, Click on "Settings" from Plugin that is Single Post Template
Now, Edit/Add/Config the setting and Click on "Save Changes" button,

Guide

Guide
Installation Upload the entire `single-post-template` folder to the `/wp-content/plugins/` directory Activate the plugin through the ‘Plugins’ menu in WordPress Create Post Templates in your theme’s folder, as described in Usage Usage After you have installed the plugin, you’ll need to create some Post Templates to use. In order to create a Post Template, either duplicate your default single post template, or create a new template file. Insert the following code at the very top of the file: See Screenshot #1 for what this might look like in your code editor Once you have created a new Post Template, either edit or create a new post, and directly underneath the post content box, you should see a new box labeled “Single Post Template”. Choose the Post Template you want to use and publish or update the post. See Screenshot #2 for what this might look like in your post edit screen

Installation

Upload the entire single-post-template folder to the /wp-content/plugins/ directory
Activate the plugin through the ‘Plugins’ menu in WordPress
Create Post Templates in your theme’s folder, as described in Usage

Usage

After you have installed the plugin, you’ll need to create some Post Templates to use. In order to create a Post Template, either duplicate your default single post template, or create a new template file. Insert the following code at the very top of the file:

See Screenshot #1 for what this might look like in your code editor

Once you have created a new Post Template, either edit or create a new post, and directly underneath the post content box, you should see a new box labeled “Single Post Template”. Choose the Post Template you want to use and publish or update the post.

See Screenshot #2 for what this might look like in your post edit screen

Reffered: https://wordpress.org/