How do you set the EASIEST settings for a single player game?

I think those are the easiest setting you will get. Try searching the forums for some good starting strategies. That helped me alot, along with playing with people who were alot better than me. also some good players post record files of their games, you can use these to see the strategies some of these players use. Some simple hints, don't expand too fast too soon(give yourself time to build up planet infrastructure before moving on to the next one), build two commercial research platforms right off the bat and research trading posts, you get a free capital ship at the beginning of the game.....use it to capture nearby planets and in the process you can earn experience points for it.

you can set the other ai players to be on your team, you will instantly win the game but you can click "keep playing" and explore the tech tree and the units and no one will attack you

Yeah dude. This game is about trial and error. It's got a big learning curve, and most of what you find out will be through losses, like what ships do what and how they work.

you may want to try "easy fortifier". the AI won't be too rough on you

Try reading my guide on AI. Maybe it will help you take off in this game.

https://forums.sinsofasolarempire.com/?forumid=404&aid=301605

Just some simple pointers.

Dun play defensively. Even on small map, there are I think around 10 planets. You need 4-5 to at least match the AI.

Know your tech tree.

Dun queue too many research at the same time.

KNOW your ships. This is very important. Different ships has different use. Usually cruisers. Some ppl use frigates but I prefer to manage less than more. Do remember there is one frigate type that is good for planet assault.

Crystal follow by metal are usually in demand. Plan accordingly and research what you need most.

Frankly this game favors offensive. Even if you use all your tactical points with 5-6 turrets and shield generator and repair platforms, they number less than 10 ships. You are better off spending on ships.

Check every income and increase their income/s. Check why some are in red and do something to keep them as high as possible.

Some pointers. Hope this helps.

You could always give yourself an AI player ally in your team.

Yeah, I was thinking that. Why not play with two computer opponents but have one of them on your team? Then the two of you can gang up on the other AI.