Unfortunately, for Minecraft Java Edition, there are no skins that will automatically incorporate a cape. However, in Bedrock Edition, there are some skin packs that come with capes included.

There are many different skins in each edition of Minecraft, including the Java edition.

How to Equip your Cape? Java Edition Open Minecraft Launcher and go to the Skins tab. Select the Skin and click on the option Edit to choose the Cape. Save the made changes and then launch the game.