You can add a media picker datatype (make sure its set to single) to your document type then you can render it like so and add your appropriate styles. In this case the "true" will make the property recursive so it will look up the tree for one being set. Its a little different depending on version, but you can find the docs here: https://our.umbraco.com/Documentation/Getting-Started/Backoffice/Property-Editors/Built-in-Property-Editors/Media-Picker/index-v7

@{
    var typedMediaPickerSingle = Model.Value<IPublishedContent>("backgroundImageAlias", true);
    if (typedMediaPickerSingle != null)
    {
        <div style="background-image: url(@typedMediaPickerSingle.Url)"></div>
    }
}

Good morning, Amir Khan.

you could demonstrate an example of this configuration.

Thank you for your support.

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