How do i combine a 2D game with Third person perspective maps

So me and my friend are trying to make a game with the same game concept as Valkyrie Profile 2: Silmeria.
We are trying to “send” the player into a third person perspective combat map through collision events in a 2D plattformer world, but can’t seem to get it done through a single project as we have no idea how to start making a game without using the project templates.

We are very new to unreal and game programming in general, so we have only made games through the templates.

So, as an update.

I resolved the problem by starting three projects. One blank, one with Third person template and another with 2d side scroller template.
I then dragged all folders from both the Third person project root folder and 2d side scroller project root folder over to the blank project root folder, and used the “Skip duplicate files” option in the file copy prompt.