HELP! Im fixing to buy yarn...oz/yd question

Found a beginner recommended sweater pattern, YAY!

I THINK Its calling for 5 -5oz [195 yard] skeins of bernat illusions or 3-10 oz[390 yards] skeins of bernat mirage

Am I correct in thinking that I can find a yarn locally that is the same oz and yardage, assuming that I do a guage swatch and it matches Ill be just fine??? And Im assuming that Ill be buying 5 skeins that are 195 yards apiece if I go with suggested brand/type??

so far Ive only bough a skein at a time for hats, and scarves have all been made from the remnants of said scarves, lol…

As long as you buy the same thickness of yarn–in this case Bernat Illusion is listed as a Bulky yarn–you can buy the same yardage as you need for the pattern and feel safe.