No, there are not canonical answers to these, except the core one -- the GM decides.
Yup. And its not just that.
Its that the game has some answers in some places that seem to apply to some things but perhaps not others? Or that they're supposed to be elided when "GM decides" they should be?
For instance, sometimes units are tightly codified, but it seems like folks just ignore/elide these constraints at their discretion. PHB 182 says Stealth Movement rate is 20 feet per round. Some Medium and all Heavy Armor rules says Disadvantage on Stealth.
But apparently, its pretty common for 5e GMs to go "nah, not applying that stuff here...Mr Fighter in Half-Plate who has to navigate a really long corridor (way more than 20 ft...perhaps 10 * or 20 * as far) stealthily...only 1 moment of action resolution and screw that Disadvantage on Stealth noise...roll Stealth normal * 1 and lets see if you navigate this corridor."
I mean, there are a lot of rules interactions here that could apply...a lot of attendant interpretations and adjudications by various GMs. But ultimately,
this GM has decided 1 action resolution and no Disadvantage (ignoring p 145 and 182 of the PHB).
I mean its different if you've got something like 4e and you're toggling to cinematic, scene-based conflict resolution for noncombat (Skill Challenge). There, the procedures (eg you aren't using the minutiae of units of movement for example) and principles that inform GMing and playing change. But its different when that doesn't exist and play is encoded task resolution all the way down. So what you end up with GM decides (and in this case you end up with your Fighter who is wearing Half-Plate + Deep investment in Dex + Stealth Proficiency + investment in Medium Armor Master to remove Disadv = losing returns on the build choices because GM decided to minimize the importance/returns on the things you invested in) and respond accordingly.
There are trade-offs in GM decides and rules systems that require significant interpretation/mediation and just ignoring stuff when the GM feels its best for play. It has strengths (pace of play being one...interesting story if the GM is a good storyteller being another) and it has weaknesses.