As captain marvellous said - You should establish the class of airspace you will be flying in during the pre-flight planning stage from the appropriate aeronautical charts
One should also check the class of airspace for any direct routings pre-flight and have a plan prepared in advance.
As for the second question - it could be a simple heading to tell you that the following are the frequencies to use or, it could be telling you that the frerquencies are for a "radio service".
If it is a "radio service" on a frequency, you will be talking to a radio operator who will relay your transmissions to the appropriate ACC and their reply will be passed by the radio operator back to you. This is most common when using HF frequencies but it is also used on VHF in certain areas.
For the full and exact answer you will need to consult the appropriate AIP which will answer both your questions.
Regards,
DFC