Sakura Micron is one of the brands we specifically mention in Lesson 0 Page 4 when discussing various brands of fineliners. You'll also find on that same page a closeup shot of a fineliner tip that you can compare to the pen you've got.

It should be fine, but without seeing a photo of the pen itself I can't confirm for sure, given what you mentioned about it being black instead of white (Sakura Microns are usually a tan colour, at least from what I've seen), so I'm not sure what you mean there.

On our discord chat server we have a channel, #drawabox-pens, where students can share photos of their pens to double check the type of pen they've got. That may be helpful to you.