I bought Minecraft Windows 10 Edition earlier and started it. When I run normally, it suddenly starts to sprint and bend, even though I only press W.
Then it is either up to the controls - reassign the keys.
In the worst case, it is simply a defect in the keyboard, but I rate the probability as rather low.
In other games, this doesn't spoil e.g. Csgo or Outlast and such
Then it's up to the in-game control, possibly 2 key assignments overlap, in your case W and ctrl.
Many have the Ctrl problem. You seem to have it too. Maybe you accidentally press Ctrl while pressing W or something. To be honest, I don't know what to do about it, but I do know it's because of the Ctrl key. You can try selecting a key for the sprint controls instead of Ctrl, and then the problem will probably be solved.
Then you should buy nh better keyboard
In my opinion, changing the controls is better because it's free.
In almost every game you use several keys at the same time or don't level it. How often do you want to change the controls in each game? Well your own decision if you don't want to do yourself the little luxury
So as a test whether it is really due to the Ctrl key. If you press Backspace sometimes, do you sometimes get rid of the last word? And will you delete everything if you write a?