Need Help Adding Photo, Text and Custom Widgets

I know adding stuff to sidebar has been answered before. For some reason I’m not getting clear info from older posts, sorry:

I want to place a photo and caption in sidebar, and potentially other things like my own custom widget names, ads, etc.

Previous answers seem to say use the plug-in made for this or add code to the sidebap.php, but I can’t seem to find one plug-in that allows for all that (I installed My Custom Widgets but doesn’t seem to add anything), and am not sure where in the sidebar.php to add what code

Thanks for any help. Can post my site/theme if the answer is theme specific