Hi, I need help in distinguishing between discharges.

I have looked around on the internet and it says that men discharge
1- Urine, 2- Mani (sperms), 3- Mazi (fluid during excitement), 4-Wadi (fluid generally after urination)
I don't really understand how to distinguish between Mani, and Mazi.

I've also read that Mani, When damp, it smells like dough; when dry, it smells like the white of egg.
Does that mean that if i wake up in the morning and if there are white marks on my clothes and they have no smell, it means that i don't need Ghusl?

I would like to learn about them, so that i know when i wake up in the morning and see marks on my clothes, if i need Ghusl or not.

Thank you.