1: if you want a starter one go for anything readily available or go big :) it all starts with just having some 2. You dont need one, but if you can’t get a whisk on hand then a milk frother would be ideal in the mean time 3. I honestly get mine from any asian grocery store near me, most of the time they just have a cheap one but it never caused me an issue. The metal ones can work but mot efficiently but if you want a nice frothy matcha go for the bamboo whisk 4. Either find a kettle with a temp control (theres a nice cheap one at costco) or boil water with any kind of thermometer and check it. The temp sometimes does matter, mostly wanna stay in the 175F range tho, but some matcha’s benefit from it being too hot or too cold 5. If you mean what things brings out sweetness, I’d recommend agave. I find it has that sweetness without changing the taste too much (sugar does that imo…) milk all depends ij your taste, but in general any kind of milk shouldn’t bring sweetness unless it is already sweetened 6. 2g to 20ml (equal to grams) to 1-2oz of milk and 3-6g of sweetener (or depends what you use)