noobs first cider - got questions

I've been reading this forum for the last few days and have thoroughly confused myself .

I'm looking to make a sparkling, sweet, hard cider. My confusion starts on how to make it sweet.

Is the general consensus to back sweeten? Meaning, let it ferment out then add your choice of sweetener. Would throwing it in a keg and in a frig be enough to stop it from fermenting starting up again?

Or is the consensus to take hydro readings until you reach ~1.015 FG. (taking a guess at hte sweetness) then stop the fermentation? If so, would throwing it in the frig be enough to stop fermentation?

I keg so the sparkling part is easy.

Here's a list of stuff I have to get the job done.

6.5 gal ale pail
5 gal glass carboy
Nottingham Dry Ale Yeast
Yeast Nutrient
Montrachet Wine Yeast
Potassium Sorbate
6 gallons apple juice.

I still have to pick up either some corn sugar or AJ concentrate or Demerera Sugar

Anyone willing to help me achieve my goal with the above tools? I saw the 'drop dem panties' recipe and it looks good but I have no idea of the time line involved.

TIA

If you have a fridge and a keg, the best way to get a sweet carbonated hard cider is add the Notty to the juice. Dont add anything else unless the sg is under 1.060, in which case add enough unbleached cane sugar to get to 1.060. Ferment until 1.005 to 1.015 to taste, cold crash and keg.

looks like i've been overthinking it again - thx