Setting up a FLSUN Super Racer and the all in one test print first layer looks like Freddy Krugers face!
My guess is the nozzle was too high for that first layer. It maybe you were going REALLY fast and the plastic just lifted before it had a chance to stick (i noticed the corner and edges look a little better, where it would have gone slower). I’ve done both with similar artifacts, though not so bad.
Whatever you do, lock the door, get a crucifix, and don’t fall asleep before you get it squared away.
I get artifacts like that when the nozzle is too low as well. When there’s not enough room to extrude all the plastic, a line next to the one that overextruded.
First, make sure that you have your steps/mm for the extruder dialled in. I measure the 100mm mark from the extruder’s intake and make a line with a sharpie. I also mark 110 and 120 if I’m not sure. Command the machine to extrude 100mm of filament and measure your marks. The 100mm mark should be right at the extruder’s intake. Take the difference between what you expect and what you got and convert to a ratio, then divide the current steps/mm by that ratio in the firmware. For example, you command 100mm of extrusion, and you find that your 110mm mark is only 2mm away, so actual was 108mm. That’s 108% or 1.08. If you had (easy example) 100 steps/mm in your firmware, you need to divide by 1.08 to get 92.6 (or 92.5926, depending on how exact you think that 100mm mark really was.) Rinse and repeat until you get your 100mm close to exactly.
Now, make sure that your Z steps/mm is good, and check that your homing is working and actually finding zero.
After homing, drop the extruder to Z=0 with a sheet of paper under it. It should lightly pinch the paper, just enough so that it’s difficult to move. At Z=0.1mm, the paper should slide more easily, and you should be able to remove it and re-insert it under the nozzle without forcing it. A sheet of paper shouldn’t be 0.1mm thick. The paper moving too easily at Z=0 or not moving easily at Z=0.1 both indicate a problem with homing.
The RepRap.org Wiki on Calibration has some good tips, and resources for getting the best out of almost any 3D printer.