Installation and server related problems

Hi Everyone

I have an error with no clue how to solve it and I’m at wits end.

Problem: Can’t save an interactive node. When I hit save, the page clears and go back to the add form. I encountered the problem with Course presenter. If I put one single text box with plain text on the first page in the presenter I can save it, if I add anything else it returns to the add form and clears.

I'm 72 so bear with me. We have Wordpress site using Sensei to deliver a mixed-media online course (not interactive). We also have license for Learn Dash. Their support sent me the link to H5P.org and I'm keen to make all our course material interactive using H5P.org.

I don't understand if we need either Learn Dash or Sensei if we use H5P. And if we need one or other does H5P interface with either or which one?

I'm so excited but am not a coder or developer so need help from this new community.

Hello,
I'm new here.
How can I install the new releases „Find Multiple Hotspots“ and „Image Juxtaposition“ for H5P on Wordpress?
I found out, that I can download a .zip on Github, but how and where should I install this file on my Wordpress-site?
Thank you very much for any information. 
Best regards,
Barbara