Controlling Two Ships in the Same Instance

[MoosyLager]

I'm trying to launch a Falcon Heavy to the Mun and I want to try make it like the actual Falcon heavy in that the side boosters and middle booster can land themselves. I've heard of writing scripts that let the ships do that themselves but I have no idea how. So is there a way I can control one of the boosters, land it, then revert to the time before I started to land that booster but the booster I landed is already landed?

Sorry, if that doesn't really make sense. It's hard to explain

[Gargamel]

@MoosyLager, As the answer will deal with a mod or 2, this has been moved to Add-on Discussion. 

[Geonovast]

Hello, @MoosyLager, and welcome aboard!

The two mods you're going to want to look at are kOS for the scripting, and FMRS for the time machine.

 

[MoosyLager]

@Gargamel sorry for that, i didn't know where to put it

 

[MoosyLager]

@Geonovast thanks for that, I've heard of kOS but I didn't know that would help me. 

[TheKSPBeginner]

@MoosyLager you can land it yourself with the help of Kerbal Engineer Redux, if you’re not good at coding

 

source: my experience

[zer0Kerbal]

TCA also has swarm mode.