can we move our bitcoin before the new fork happen?
Yes, you can move it and the best wallet for it is through electrum. There are some supported wallets that are indicated in the btcgpu.org but they are now being DDOS attacked.
and after?
Just keep it there and wait for the hard fork to finish.
how it work exactly do we risk to lose our coins because of replay attack? from 25 october to 1 novemeber there will be this new fork i want to know thnaks
There's no risk on it and it's totally a free coin so while you are just watching or waiting for the hard fork to be done make sure that the wallet you will be keeping your bitcoins, you have the private keys for exporting / importing purposes.