Lightroom CC will not run on 32bit operating systems.
Lightroom 5 will run on 32bit operating systems.
No. LR CC only works on 64 bit systems running 64 bit operating systems.
If you have a subscription to the Creative Cloud Photographer plan you can install LR 5 on that plan. In the CC desktop app if LR 5 is listed as a Trial just install it and then Sign In using the same Adobe ID, Email Address, that is used for the Photographer Plan subscription.