Do I have to make a back up copy every time I make a transaction? In other words when I make another transaction but I only have the original backup when I restore the backup does it only show the amount from my original transaction or will it be updated to the latest transaction if I've made several transactions since my back up?
You just need to backup your private key or your 12 words nothing else

The whole network keep a full backup of all your transactions

If your wallet make new bitcoin address for each transaction you need to keep a backup of your new private key as well