If I do this is it safe ? or could it then be robbed ?
If the code is a private key, they can and will steal your coins. Don't do it.
2, Some people tell me I have a “pre hard fork coin” and as such it is worth lots more money.
I do not know what pre hard fork is, So is this true ?
There have been two hard forks. These are splits in the Bitcoin blockchain which essentially leads to having two separate currencies. If you hold BTC at the time of the fork, you also then own the same amount of the new forked coin.
This means that the value of your physical coin is roughly equivalent to the
value of Bitcoin, the
value of BCH and the
value of BTG,
all together.
If so should I mention this fact in the sale as it still has over 4 days to run?
Yes.