I think you may be getting a tad confused here.

Levels and tiers are completely different. Level refers to the NPCs contained within, and how
much damage they will do and how much it will take to kill them. Tier refers to the type of POI. The Zirax Sector command is a Tier 5 POI, The Ghyst Military Bunker is a tier 4, the Drone base (NOT the temporary drone base) is a Tier 3 (as examples). You will NOT find the Tier of a POI written down anywhere within the scenario, it's knowing what POI is what and how each POI is built up, how many defensive weapons? Does it have a shield? Does it have a basement section? And so on, and so on. Each tier builds on the previous. From Memory, a Tier 3 would have a MINIMUM of 12 turrets, a shield , and laser fences.
Drone Base (T3), Missile Base (T3), Military Bunker (T4), Fusion Power plant (T4),
Sector Command (T5)

(This is from Oct last year, may have been revised, but is still pretty current as far as i am aware)
Tier 1 POI = 1 Core (Most common POIs, 4 turrets, no shield)
Tier 2 POI = 2 Cores (8 turrets, shield, walls, no underground)
Tier 3 POI = 3 Cores (12 turrets, shield+, walls, underground level)
Tier 4 POI = 4 Cores (16 turrets, shield++, walls, multiple underground levels)
Tier 5 POI = 5 Cores (20+ turrets, mega shield, multiple walls, extensive buildings, multi-level dungeon both up and down)

From what I understand there no tiered space stations, you would only find data cores on Zirax OPVs, again tier 3 and above. Imerat-Class Destroyer, Kamirat-Class Battlecarrier, Kythera-Class Battlecruiser, Tovera-Class Dreadnought.

Thank you very much, i didnt now any of this things, but i wanna ask something, what is OPV and which pois has good loots thats will worth to take your time and resources to take down? i dont now which poi is what tier, lastly where to find high tier planetary pois, i have a cv carrier thats has a advanced warp drive so i can go anywhere as ı now, bu i dont know where to look for high tier good looting poıs, is there any specific zones or locations for thats?

It's all random based on the seed generated when you started your game. So where I find stuff will be different to you.The above is a guide to help you. All I can suggest is to explore the galaxy, and then explore some more!

OPV is Orbital Patrol Vessel - ie any enemy vessel that you would find in planetary orbits or solar systems.
PPV - Planetary Patrol Vessels - ie any enemy vessel that you would find on planes

You can get Datacores from Tesch Overlord POI on Tesch planets and also on Sector Command for Zirax. Overload has 3 and Sector Commands has 5. There are other Zirax POI that has them too but I haven't tried them and can't remember which. Personally I prefer the Tesch Overlord for datacores. You don't need to clear all the way to the end for them. But your millage may differ from mine. I use a small SV with rockets to take out some of the "tanks" inside. The rest I use a rocket launcher. Instant reload weapon mod on rocket launcher is amazing.

Thanks, i wonder what is best way/POI for grind quantum cores?

引用自 HimitsuArashi：

Thanks, i wonder what is best way/POI for grind quantum cores?

Legacy POI would have the most Quantum processors. Personally I'd say Legacy Infector OPV are the easiest one, however I don't know how advance your ship is.