(New guy here)What to select for a new project that will have 2D AND 3D modes?

Hi,
New to forum, I read thru the CoC so hopefully I don't break any rules with this post.

I am looking to make a mobile game, but I want to have it have multiple modes.

- Menu mode, where the player is in a 2D (canvas?) that can perform things for the game using resources, timers and other very simple 2D buttons.
- 2D game mode, where the player can play his character/units in a 2D isometric style that uses strictly 2D sprites (even if the original models were 3D, but made into 2D sprites, similar to how D2 was made).
- 3D game mode, where the player can play like a typical 3rd person 3D RPG game.

I wanted to do this mainly because I found games that are true 3D often only run well on very high end flagship phones.

There are other mobile games that have done this, partially, where the menus are 2D, but thru the menus they can access another part of the game that is seemingly rendered or run in full 3D.

So, when I try to make a new project in Unity, the templates it gives seem to be either one or the other.
How do I go about setting up a Unity project where I can do all 3, menus, 2D game, 3D game?

I appreciate any help!

 

you can do everything in both modes, it only sets some suitable default settings for each mode:
see here at "2D vs 3D mode settings"
https://docs.unity3d.com/Manual/2DAnd3DModeSettings.html

if most of your images are going to be for 2D, then it saves time to set it as 2D mode (texture import settings will be then ready to use for 2D UI/Sprites) etc.

You can also switch that setting anytime from Project settings.