I will assume your VHS has not got a digital tuner and your freeview is a single tuner.
Firstly, make sure your recorder, box and tv are connected properly - like this:
http://www.dtg.org.uk/consumer/connection_wiza rd.html
Now you will have to find out which 'channel' your freeview is using - turn everything on and set the freeview to a digital channel such as BBC3.
Make sure are watching tv through your video, change the channel on the video to zero and using the channel change arrows change down through the AV and EXT settings until BBC3 shows on your screen. This should tell you if it is AV1, EXT2 and so on.
To record freeview you will need to manually set up the time and date on the recorder with the channel being the correct AV or EXT.
The freeview box must remain switched on to the channel you want to record, otherwise it won't work.