It is the same as before 23.4.
The "Project Panel" is the one with your project information in it (clips, sequences). The Effects are in the Effects Panel. Those 2 panels are grouped with several other panels. You can restore the ones you've closed by clicking on the Workspace icon and picking reset to saved layout.
But to deal with your styles, you only need the Project Panel. If you have created other folders (bins), they may be inside those.
If you don't see the problem, give us a screenshot.
When you create 2 styles with the same name, there is no difference in the Project Panel. But they appear to be sorted in the EGP and the Project Panel by the order they were added.
To avoid accidentally deleting the wrong one, in the Project Panel, rename them. For example, if they are both called "Red Fill," Make the top one in the list Red Fill 1 and the second one Red Fill 2. You probably have Red Fill 2 (the one you created last) applied to your caption track. You can check this by selecting one of the captions and see in the Essential Graphics Panel which style is applied. In the Project panel, delete the style you don't want.
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