Could someone explain what the markers do in map view

@XjayIndustrys, glad to help.

@eonn44 Thank you, I didnt know that! TBH i was asking about the bits that pop up on your course in map view, Thanks!:)

here's a brief rundown of the markers:
the green arrow is your apoapsis (the highest point in your orbit)
the orange arrow is your periapsis (the lowest in your orbit)
when getting planning an encounter, there are two markers that show up:
the first one (the white one that looks like a rocket) is the visual representation of where your spacecraft will be closest to your target for a closest approach. the second one (the other white one that looks like a satellite) is the closest your target will be to you visually at your closest approach.
additionally, when in the map view, there is a box on the right that has all of your orbit details. to save "space" (pun intended) in this post, I won't detail each here, but at this Wikipedia article: https://en.wikipedia.org/wiki/Orbital_elements. everything in the orbit details is described in great detail and then some on this page.
note that if you are just starting out, I wouldn't worry a whole lot about everything in the orbit details box except inclination. your Inclination is critical for things like rendezvous, and so are the rest but the rest are for calculations like delta-v required for something, transfers, etc. Hope this helped, and happy flying.