You dont. There isnt much you can do here besides carefully trimming your plane and timewarping at 4x, I am afraid.
Maybe MechJeb or similar Mods can help

There are MODs for that...

Waypoint Manager...

https://forum.kerbalspaceprogram.com/topic/194876-112x-waypoint-manager-new-dependency-added/

MechJeb...

https://ksp.sarbian.com/jenkins/job/MechJeb2-Dev/

Bon Voyage...

https://forum.kerbalspaceprogram.com/topic/172447-ksp-1123-bon-voyage-141-2022-10-02/

Pilot Assist...

https://forum.kerbalspaceprogram.com/topic/184277-110-pilot-assistant-atmospheric-piloting-aids-1134c-2020-08-18/

Atmosphere Autopilot...

https://forum.kerbalspaceprogram.com/topic/124417-180-1125-atmosphereautopilot-161/

KOS - Kerbal Operating System...

https://ksp-kos.github.io/KOS_DOC/


Check those out and see if any of them get you where ya want to go.

Go into orbit

Bring up Kerbnet screen and orbit over point you want to target and set a marker there

In map screen set your marker and activate navigation, this will put the marker on your navball

put your orbit over spot and de orbit so you land there. Watch navball and retrograde marker, set SAS to retrograde.

The marker will be dead center when you are over it, make sure navball is set to "Surface"
retro burn to adjust.

All this is in basic game.

Flying a plane then I suggest doing a sub orbital hop and basically plan it the same way.

NOTE - you can set a marker beforehand with any sat with kerbnet, then use it to guide the plane direction

Practice.

The hardest part is getting initially near the target, fine tuning your descent with the navball isnt normally to bad. Im not that great but I can get within 50m pretty easily. Im not good enough to actually land on something like a docking port.

This is a skill you need to learn if you plan on having a base somewhere like on the mun and going back and forth between it.

I start by going to the lowest orbit you can and then making a maneuver node a bit before my target so I have time to decelerate towards it.

It's hard to explain how to use the navball without showing how to use it. If you can dock two vehicles in space then you should be fine with it.

This is actually a skill you should be learning to use during the early kerbal "survey" missions.

People arent actually spending 3 hours to fly across are the ocean are they lmao. I usually go suborbital so I can achieve those high speeds and then descend near the area I need to survey. Kinda like how real intercontinental ballistic missile rockets work.