Lightroom export settings

That depends on many factors. The 1st question is .... why are you not using the print module in LR? There's a bit of a learning curve, but once you get it sussed out the best prints may not ever need exporting at all.

If you do need to have your image files printed somewhere else, then the export settings need to be tailored to that specific printing need. The nice thing is that you can save export settings as presets. So the next time you need to export files for the same use, you can just pick the preset.