Partititoning the hard drive after Ubuntu installation

Based on your comments above you have a primary partition (sda1), an extended partition (sda2) and within the extended partition you have a logical partition (sda5-swap).

It is not clear if you want to make a primary or a logical partition. In either case, you will need to shrink the sda1 first to free up some space.

In gparted you can click on the sda1 partition and drag it's right edge to shrink it.

Once you have some unused space, you create more partitions.

To create a logical partition you have to shrink sda1, expand the extended sda2 to cover the newly created unused space, and create new sda6 logical partition inside sda2.

You can try this in gparted, nothing will be done until you click Apply.