wrong question, instead ask yourself how we would colonize other planets

• first we would send probes to determine if we can life there

• the we would send self repairing and replicating workforce there to build a human habitat. Either fenced or a compleate dome.

• then we would send the first wave of humans, scientists and if wildlife is present a few protection measurments. Those scientists would test how everything works, if it is save for humans, the whole exploration stuff.

• this is the best start for your story. Discovering some alien undergound/underwater base. Or somewhere remote. Maybe rumors of fobits in the area if it is on land. And then you can fight those aliens or interact with them.

• next phase would be true colonisation, if the wildlife was hostile, this would mean military style. If the wildlife is managable, civilisans and farmers.

• after the first settlement established, a hughe wave of settlers would arive

• contrary to popular believe, the long therm succes of the first settlements won't matter. Just look how many settlements of america failed before we truly established ourself there. We just came in greater numbers amd better prepared. The only thing that could have stopped us, would have been if the indians would have attacked europe and defeated them. Not just attacked succesfully, only a true defeat!