Crawl under & look a the tranny pan...you'll see two "drain plugs". The one closer to the ground is the drain, the upper one (recessed into pan) is fill/check.
Take her for a little drive to get the tranny up to temp. Park on some level ground, apply parking brake, put in park, let idle, crawl under & crack the ck./fill plug, remove slowly.
There should be fluid coming out if it's full, if no fluid, get a hand pump from NAPA that screws on to the top of your favorite brand & fill it until there is over flow.
Replace plug.
I think most synthetics are compatible w/ regular ATF...a little label research should be done though.