How to insert a link to Bitrix?

Question

1C-Bitrix

For example, I have a block with a video, how can I set my link to the video through the admin panel?
At the moment the code looks like this. I'm interested in what needs to be inserted into src in the code and how to display it in the admin panel? I'm new, I still don't understand

<div class="mainPublicationsVideoListOne" id="<?=$this->GetEditAreaId($arItem['ID']);?>">
      <div class="mainPublicationsVideoListOneCover">
        <div class="mainPublicationsVideoListOneCoverImage">
          <iframe width="560" height="315" src="ЧТО ТУТ ВСТАВИТЬ?" frameborder="0" allow="autoplay; encrypted-media" allowfullscreen></iframe>
        </div>
      <div class="mainPublicationsVideoListOneCoverTitle"><?=$arItem["NAME"]?></div>
      </div>
      <img src="/images/style/video-sizer.png" alt=""/>
    </div>

Answer 1

If the vidos is inserted in the admin panel simply by a link, then either the link is in the already set properties ( $arItem['PREVIEW_TEXT'] или $arItem['DETAIL_TEXT']), or there is some property (created), then it will be necessary to select this property in the component settings for display and display in the template

$arItem['DISPLAY_PROPERTIES']['НАЗВАНИЕ_СВОЙСТВА']['VALUE']
либо просто $arItem['PROPERTIES']['НАЗВАНИЕ_СВОЙСТВА']['VALUE']