nineteentool, Welcome to the forum.
I take it that by 2d objects, you mean 2d pictures. There is no direct way to import 2d pictures in Bryce. But you can apply a 2d picture as texture.
Create a 2d object, Select it and go to the material lab. Click any attribute in the A column and a random texture swatch appears at top right. Click button P button to change texture source A from a procedural texture to a 2d pict texture. Click on right side button from the two top left ones in the same small window to access the 2d pict library.
In the 2d picture library, you can load your 2d picture and a alpha version of the same picture to get it as a texture.
For a detailed tutorial on this look here:
[http://calyxa.best.vwh.net/~calyxa/pearl/materialtut/picts.html]
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