I use this template code for uploading images here. (I would not know if it would work with the NaturalMedicine frontend though).

<center><img src="https://cdn.pixabay.com/photo/2014/05/03/00/46/notebook-336634_960_720.jpg" /></center>
<center><a href="https://cdn.pixabay.com/photo/2014/05/03/00/46/notebook-336634_960_720.jpg">Pixabay Image Source</a></center>