Use presentation ID in place of <presentation_id>.
Replace <width> and <height> with desired size of the embed in pixels. SlidesLive player will expand itself within these dimensions.
<iframe src="<https://slideslive.com/embed/presentation/><presentation_id>" width="<width>" height="<height>" allow="autoplay; fullscreen" sandbox="allow-forms allow-pointer-lock allow-popups allow-same-origin allow-scripts allow-top-navigation" frameborder="0" scrolling="no"></iframe>
IFrame only embed cannot be responsive. If you want responsive player use Javascript embed.
Zooming feature will not work properly because embed size is fixed.
Analytics will not work properly for IFrame only embeds especially when there are multiple embeds on the same page. Every embed can be shown as watched by different user in Analytics even though the same user is watching all of them on the same page.