I have a wine that's been on primary fermentation for 10 days and still haven't seen any activity in the airlock. I think that the reason is the sugar and the yeast needed to be added. I saw in some YouTube channels that in one gallon of Welch's grape juice I should take out two cups of the juice out, then I have to add half a kg of sugar and one teaspoon of yeast to it. In fact, I did not remove the two cups because I'm using a bigger container.
So shall I add like 150 grams of sugar and 1/3 of the yeast to it?
Note: I'm using bread yeast, and my room temperature is 21°C or 70°F.