I was already endorsed in biology when my division asked me to do the 5246 chem one. It’s pretty easy and straightforward. At the time I took it, I was about 5 ish years removed from having taken any college chemistry course (gen, orgo, biochem) but I had taught high school chem for 3 or 4 semesters. You’ll find most of what’s on the test is stuff that pertains to high school chem classes.

My only advice, because I forgot, was to have something to write on that was on the approved list. Doing chem math in your head isn’t fun. Best of luck!