You should be able to access all systems other than ORSEE & XNAT using the login provided to you by the Charité Berlin.
Sometimes, the Charité doesn't grant interns the ability to log into foreign systems using the credentials of the Charité. If you are facing this issue, please contact the Charité's DFN AAI administrator Mario Severing mario.severing@charite.de.
You won't be able to access the firewalled systems (PAMS, XNAT, Neurowiki) from outside of your institution's network. In such cases you should turn on the VPN provided by your institution.