From my experience, the things you'll probably struggle with are bed leveling, first layer adhesion, temperature settings, and speed settings.
Bed leveling: One of the first things you need to do is make sure your bed is level. Exactly how to do this will vary from printer to printer. Mine for example has 4 screws you an adjust on each corner of the bed to raise or lower each corner independently. What you'll want to do is heat up your printer, center your nozzle over the middle of the bed, put a piece of paper under the nozzle, and then home the z-axis. Adjust your z-stop until the nozzle tip is just barely touching the paper: you should be able to push and pull the paper without it bunching up, but still feel some contact between the paper and the nozzle tip. Move the paper and extruder to each of the 4 corners of the bed, and make sure the "feel" of the paper between the nozzle is the same at each corner. Adjust your heights until it feels right, and then double check the center and all four corners again.
First layer adhesion: This is the one thing that'll make and break your prints more than anything else. If you can't get a good first layer, you can't get a good print. There are three things that go into a good first layer: setting your z-height right, bed surface, and chemical adhesion. Setting your z-height is closely tied to bed leveling, and you should periodically check with the paper trick to see if your heights are still good. Some print surfaces stick better than others, and you should experiment with a couple different things to see what works. Your printer will probably come with something that works fine, but common materials include glass beds, painter's tape, kapton tape, commercial materials like BuildTac, PEI plastic sheets, and aluminum. Finally, if you need even more grab, you can often treat your bed with something to make it stick even better. Common treatments include hairspray (I recommend Aquanet Unscented), glue sticks, and (for ABS) a slurry of acetone and ABS.
Temperature and speed settings are something that usually comes from experimentation. It seems that the most common benchmarking test nowadays is this guy, so once you think you're good to print you should try to make one. However, you can dial in on common problems with smaller prints designed to highlight one thing at a time. The 5 mm steps is usually a good print to test accuracy, overhangs, and how well you print fine features. Something like this can show you how well your bed is leveled, how accurate your X and Y calibration is, and make sure your axis are square with one another. You can also test your overhangs, or your bridging with more specific tests
Thankyou if you made it till hear I know that was a huge message.
