In a word: "Nope!" The game was not designed to work like other open-world games (Elder Scrolls, Assassin's Creed, FarCry, GTA, etc.) It's not really possible to "100% the game" in a single playthrough. Rather, TW3 requires the player to choose their path at certain junctions, and that choice will close off other pathways. That can also affect what side quests become available, whether certain characters live or die, etc.
Also, the game works in unspoken "chapters". But rather than interrupting the action with cutscenes or title screens, they just blend seamlessly together. However, when the player advances the main quest from one "chapter" to the next, the gameworld is advanced, and that means that certain side-quests will become unavailable while new ones open up.
So, best bet if you want to see as much as possible is to wander the world, gathering up every quest and Witcher contract you can find. Complete everything that's at or below your level right away. Once you're left with only high-level quests and contracts (orange or red level), advance the main story. Bubble-rinse-repeat.
My personal take is that the game works best if played with a fairly narrow focus on the main quest. Geralt can't be everywhere at once, and he's trying to find Ciri. He "needs to eat", so to speak, so he'll grab the odd contract for coin as needed. He'll also help out a friend in need or aid the odd NPC if he stumbles into trouble...because...he's Geralt. As for the other side-quests or pathways -- those are for future playthroughs. (I'm currently in my 6th run, and I'm STILL finding new things.)
