Q: Apps Store allows to sign in but does not allow update or purchase

iLife came installed on my new Macbook Pro. I am being prompted to download two udates, one each for iMovie and iPhoto but Apps Store, despite permitting successful log-in, keeps on demanding password over and over again. To resolve the issue, Apple has sent me free codes for iLife. If i uninstall iLife and try to reinstall it using new codes, will Apps Store allow that? As i am totally new to Mac, I am reluctant to delete any application.