Hi Furton and welcome to FT!

The miles are poor value for this sort of redemption - as per Hiddy's comments.

However you don't actually need the miles in your accout to do a dummy booking - you get to see what's on offer, which flights and times are available and only went you go to the next screen will it complain (in nice red letters) that you don't have enough miles.

For a single BAEC account those miles can be used to buy a ticket for anyone.

For info BA have household accounts where a condition exists that miles can only be redeemed for members of that household and nobody else.