Hello @Ronn2d2,
The Nokia Lumia 830 uses a nano sim which is smaller than the micro sim used in the LG G3.
If you want to switch back and forth between phones, you can get a nano sim from Rogers retail and buy a nano to micro sim adapter. Not sure if the Rogers store would sell the adapter but you should be able to buy it from a third party cell phone shop or online. This will allow you to use your nano sim via a sim adapter in your LG G3. If you google "nano to micro sim adapter", it will give you an idea of what it looks like.
Hope this helps 🙂
RogersHassam