for macros they are very easy. here is the all list:
https://github.com/unaio/una/wiki/Macros
click on individual macros and you may see the parameters to use with them.
Some examples:
to embed a specific blog post to a text area, (raw block or into any html editor posts, pages etc)
{ { ~bx_posts:entity_text_block[contentid of the post]~ } }

to embed videos of an author:
{ { ~bx_videos:browse_author[Author ID]~ } }