SharePoint Online - Web part help

Looking for a matrix or spreadsheet that shows the various webparts, functionality and limitations. I am spending lots of time trying to figure out each web part and on deadlines.  Appreciate your help if there is a document or web page with this detail.  It's not on Microsoft's!

example:   hero web part, what type of images can be used, hyperlink yes/no, text char limit 40!

call to action ( found this online today)     -image will be rectangular and not square (or any other shape) regardless of the image that you use. If you want to have a nice square call to action button, this web part currently doesn’t support it 

etc.

etc.

Thanks.  Maureen