Welcome.
PLA type: others may have differing opinions but in my experience PLA from different manufacturers are much the same and any will do so long as it isn’t something that has a different formulation like silk or glow in the dark.
Layer thickness: this means layer height not wall thickness. And thicker is better for strength. So with a .4mm nozzle .0.25mm or even 0.3mm height will be stronger than 0.2 - and faster to print.
Infill: you can try it, that’s the fun thing about this stuff! Print something with each of the 2 infills and wall setting and see which is harder to break. I personally left it the way it is in the documentation - it’s tried and tested by Ryan
Top and bottom layers: 4 is fine and the default infill is fine.
Good luck!
One more thing. As it’s a brand new printer - before you start printing everything satisfy yourself it’s calibrated and square. Because the parts are so big small misalignments can cause big problems. Have a read of this and check your printer is squared Der Froschkönig - Lowrider 3 in Oldenburg, Germany - #178 by vicious1