On a 2009 MacBook Pro, you can experience 10 hours of usage before needing a recharge.
On a 2009 MacBook Pro, you can experience 10 hours of usage before needing a recharge.
You're looking for a compact, portable laptop that works as a secondary device. The battery cost in the UK is around £25, so it should be affordable.
Visit the support page for Apple: https://support.apple.com/en-us/HT201468
It seems you're facing a challenge. You might consider creating a Windows 10 USB drive and installing it manually. However, you need to be sure about the steps to avoid losing your MAC partition.
According to @NelizMastr, you must use a DVD to set up Windows, after which you'll need to install the Windows 7 drivers using compatibility settings. Windows 10 should function on older Macs as well.