To be fair, that really depends what you use your PC for. Looking at youtube without a profile, and reddit and the news, playing music, offline games. You will be 100% fine. If you have to log into somewhere with sensitive data, don’t. But as a secondary device you PROBABLY will be fine. Requires significant discipline, to not accidentally log into facebook on it though.
Highly unlikely. For all intents and purposes it is impossible to create any system, that is anyonymus and trustworthy. And in voting one is exactly as important as the other. If you tried to make electronic voting, keep in mind, that ANY DEVICE in the chain that runs even microcode, or has any form of firmware is suspect. Better cryptography almost makes things worse.