Where is "edit"-> "group" in Shop?

Look, I’m trying to use this for something pretty simple and even the simplest commands seem to be out of reach. Where is "edit’?? Where is “group”?? Is there any reasonable tutorial for Shop?

If you want to edit a group, right click on it and choose Edit Group. Or simply double click on the group to open it for editing.

To make a group, select the entities you want to include in the group, right click on it and choose Create Group.

OK, I double clicked the “group” (which I wasn’t even aware of having made). Everything lights up, including the little person icon. All shows as “untagged”. I’m simply trying to get outer walls as a “group” with nothing else, and put it in the “tag” outer walls. Have been trying to do this one frigging step for an hour.

I don’t think there’s much that specifically covers Shop, but the basic stuff in the tutorials is the same in Pro and Shop, just with a different user interface. Start here: https://learn.sketchup.com
Having said that, there probably should be tutorials for the web version, especially for beginners to explain the user interface.

Click on Tags icon at the right, click the ‘+’ to create a new tag and name it “Outer Walls”. Select your walls, right-click, “Make Group”. With your new group still selected, open the Entity Info and click on the current tag (probably Untagged) and choose your newly created “Outer Walls” tag.

If you share your model here we could show you how to do this with your model.

You can also add un-grouped items to a tag.

But you shouldn’t!
Only groups, components, dimensions etc should be assigned a tag, never assign raw geometry to anything other than Untagged. (unless you really know what you are doing and it’s for a very specific purpose.)