Don’t mind me; forum newbie here…
According to all the information I can find via EricTheCarGuy, ChrisFix, and the like, transmission fluid is meant to be a light pink or red. From what I’ve gathered from those sources, nico, and from what you’ve described of your car’s state, the color you’re dealing with indicates generally old fluid.
That being said, flush it out entirely, or at the least get it partially changed (alongside the transmission fluid filter, if one exists for that model). I believe your transmission will thank you.