I mean... you could do this, but it would completely depend on your threat level. The problem with this idea is that using your computer in any way that's remotely convenient or normal is impossible. Eventually everyone screws up/gets frustrated/let's their parent or SO use the machine. Right then all of this is mute.

If you're this level of paranoid any email account used more than a handful of times has to be burned and never touched. You definitely should not ever access a cell network with a smartphone, which has to be burned as well every week or so. Social media use is also dead. If you don't use social media because of security concerns, that's fine, but 2.5 billion people do, so you're probably in the minority.

If you're going to whistle blow there are a bunch of other steps you should implement, running TOR being one of them, Tails if you're that high up of a risk (hint: you're probably not). If you're at that level 1.) you should be doing everything from various public wifi networks in cities nowhere near you and 2.) the fact that you downloaded TOR is not what anyone's interested in anyways, it's what you're saying and doing behind it.