It is important to use the pattern's recommended 'weight'
yarn, especially when you are a NEWBIE!
Old timer knitters
can tweak a pattern to fit the wrong weight yarn...but there are even limits on how effective that is!
Very important to make yourself
knit a 4"x4" gauge swatch...with the recommended needle size first...and then if your swatch does not measure to the pattern gauge...adjust your needle size up, or down...and do that swatch over. This 'gauge swatch tweaking' is how old timer knitters test to see if they can make an 'uncalled for yarn' fit a pattern. Sometimes it works out...sometimes you have to give it up.