How to install a Specific Forge Version on your Minecraft Server (1.17+)
Downloading the Server JAR
Head over to the official forge website and select the version you'd like to install. In this case, we will install a specific version of 1.19.4

In this case, we will install the 45.0.66 version of Forge 1.19.4. Click on the "Installer" button.

Open the JAR file that you just downloaded and click on the "Install Server" option. Then, select the directory to install the server into.
Note: Make sure that the folder you are installing it is empty, otherwise it will not continue.

Finally, click "OK".
Installing the Server JAR
Inside the folder, a folder called "libraries" will be generated. Right-click the folder and compress the folder into the .zip file format.

Upload the .zip file you created and upload it to the root of your server using the file manager. You are also able to use SFTP for this.
Once uploaded, click the 3 dots on the right-hand side and select the "Unarchive" option.

Head over to the "Startup" tab on the navigation bar and find the "Forge Version (1.17+)" option.

Enter the version inside the input box. In this case, we will type in 1.19.4-45.0.66.
Start the server. Your server should now be online!
If you require any further assistance, please create a ticket here.
Created By: Greg K
Updated on: 20/06/2023
Thank you!