Q: Can I install on MacBook Windows 32-bit version

Please find your Mac year/model in Boot Camp: System requirements for Microsoft Windows operating systems - Apple Support matrix and check what versions of Windows you can run and the specific drivers you need.

Windows Update requires internet access to contact M$ servers. If you do not have Bootcamp Drivers loaded and installed, some of your Apple-specific hardware will not work.

The version of Bootcamp Assistant and Bootcamp Drivers can be different. It depends on the version of Windows you are planning to use.

It would help quite a bit if you can provide your Mac year/model.

From the same link posted earlier,

You can install W7 32-bit, but you will need to use Boot Camp Support Software 4.0.4033 drivers. You will need to run Bootcamp Assistant 4 from an older version of OSX. You can install OS X: Installing OS X on an external volume - Apple Support which has BCA 4.x and then install W7 32-bit.

Boot Camp 4, OS X Lion and Mountain Lion: Frequently asked questions - Apple Support should also help.

You do not need to uninstall BCA 5.x. What version of OSX do you currently have?

From Boot Camp: System requirements for Microsoft Windows operating systems - Apple Support

You can also download Boot Camp 4 or Boot Camp 5.1 support software from the Apple Support website. Boot Camp 5.1 requires OS X Mountain Lion v10.8.3 or later.

Do you have the ability to install Lion/Mountain Lion?