You’re on the FliteTest forums and most of us build foam planes, so your answer will be skewed.
I got into foam planes because I enjoy building and I can’t stand the thought of wrecking an expensive store bought plane. Wrecking and rebuilding a foam board plane only costs a few bucks. As a result I don’t feel awful when I crash. Also, I can take much bigger risks. The other day I was doing a 6 foot inverted run down the runway and at the end I pulled the wrong way and smashed my plane. I didn’t care though because it was an old model that I halfway intended to wreck anyways. Now I have a pile of electronics to build a new plane.
I see the advantages of other styles too. Pre-build planes have fewer issues and frequently fly better because everything tends to be better aligned. 3d printed planes look very good but don’t survive crashes well. They’re all fun.
To learn 3D, the FT3D is a great place to start. It's easy to build & repair. It will do everything your skills will allow. When your skills advance, the Edge is the next step. The Edge looks a bit better, but is more difficult to build & repair.
I would say either the Tiny Trainer or <https://store.flitetest.com/ft-tenet-v-2-duo/>
or, if you can find one, a good EPP trainer kit (basically you can throw it hard at the ground and it bounces right back) could be even better as they can take a lot of abuse and go right back to flying.
the 2 things your looking for in a trainer are: easy to repair/hard to break (your going to crash), tame flying style (IE big wing/low wing loading/etc)
3d prints break messy
balsa breaks messy and is more work to put together then 3d prints
RTF/ARF - depends on the make of them (IE materials made out of)
foam - depends on the foam - but generally is going to be the most easily repair from a rough crash.