Partition Table confusion

Hello,

I am a bit confused to understand partition table on my system. Currently, I am studying for RHEL9 exam. one of exam topic is about partitioning, so I was playing around with my system. I did fresh install and deliberately left around 4Gb disk available while partitioning.

When system rebooted and I was looking for 4Gb. However, I cannot find anywhere its just showing me 1024M as Sr0 Type as rom.

I am confused now. Thank you in advance

rav