Looks like you're off to a good start!
Every time you go out you will be developing your eye. Identifying beach gravels can be very difficult because they have been rounded and shaped by water and, in your area, have been brought from elsewhere by Glaciers. Yes, the corals and Petoskey Stone will be easy to recognize but you will probably develop a big pile for "Others".

One of your pictures is of a large rounded cobble, that looks pretty much like a rock, with cool pieces of green that resembles Jade. There could be a half dozen different minerals in that rock and each would have to be identified. That's the difference between 'rocks' and 'minerals'. Rocks are rocks because they are a combination of minerals.
You have a couple pictures of rocks with yellow-ish white interiors.
Is that quartz or calcite? A real easy way to tell would be a "Scratch Test". The "Hardness" is very important so learn about Moh's.
And even though you are collecting mainly on shorelines, ie; random assortments of rock,  learn about your local rock, where it is and how it was formed. Besides for the fact that it can be interesting stuff to read about, the knowledge will help greatly with your rockhounding.

And I know you've heard all about these;
https://www.michigan.org/article/guide-finding-michigan-yooperlites

And, have too much fun!