I tried your save.
For a first game, difficulty 8 is high, and the "snake" map layout can be challenging: it looks cheaper to defend, but it restricts your options to navigate and expand your territory... You have a Mk4 planet with an AI Magnifier on one side, and a Mk2 planet with a Troop accelerator + 98 sniper turrets + Ion cannon + 1200 ships sleeping on the other side
I would take down the ion cannon, and datacenter behind the Mk2 planet Akka with the raid frigates, and hope the AI does not hit back too hard after that... 100 AIP is too high for me in early game. Unlock Fusion tech Mk2 + 3 other techs Mk1 . Replace 1 or 2 inner logistical stations with an economic station for metal income.
Then I would try to lure some AI ships on my planet (put a military station if necessary, add some tractor turrets near the wormhole to lock the incoming AI ships in range of all our turrets), until I can take down the guard posts (hit and run before losing too much)
For a less frustrating game, you could try diff 7 on an "X" or "realistic" layout map ?