You can find it in the real Garmin G1000 pilots guide.
For Synthetic Vision press the PFD softkey, then press the SYN VIS softkey, then enable all that stuff (PATHWAY, SYN TERR, HRZN HDG, APTSIGNS)
For the weather radar you need to navigate to the radar page, press the MODE softkey and then either put it in standby mode or start with weather or ground mode right away.