Sherryl, I used to be a technical writer for Acer.
Laptops are far harder to upgrade than desktops, as the parts are more specific. Windows 10 is designed as a 64-bit system, while Windows XP is designed as a 32-bit system. The free upgrade was designed for Windows 7 and 8.1. I was writing on two Windows 10 forums and noticed that Windows 7 laptops had more trouble with Windows 10 than any other type did.
The only real thing you would gain by upgrading to 10 (which your machine probably cannot do) is access to the Windows Store, and you wouldn't be able to run most of the programs there anyway.
Your best course is to keep your anti-virus updated and stick with XP until you can buy another machine.