straight -> heterosexual and/or hetero romantic
cis -> a person who identifies with the gender they were born as
straight is a sexuality and cis is a gender identity! they are different things from each other :>
pansexual means a person who feel sexual attraction towards to people regardless of their gender (as there is more than two genders) (panromantic is the romantic attraction version of it) !
genderfluid by the gender wikia:
Gender fluid is a gender identity which refers to a gender which varies over time. A gender fluid person may at any time identify as male, female, neutrois, or any othernon-binary identity, or some combination of identities. Their gender identity can vary at random or in response to different circumstances. Gender fluid people may also identify as multigender, non-binary and/or transgender.
hope this helps! its not ignorant or annoying at all :> im glad you asked!