>>10697113So, out of curiosity how old are you? Not trying to insult you, just give some hopeful constructive criticism.
1) nubs should be handed in three stages. A first cut off the runner about 2.5 mm off the part, a second cut to remove the majority of the nub, and a third with a razor/file/sand stick to totally get the part flush. I recommend a small razor since you can minimize the chance of scuffs. Do not use nail clippers. Get some proper flush cutters from your local hobby store.
2) apply even pressure during assembly. Those gaps are insane, they should not be there at all. Some low quality kits may have gaps, but carefull modeling can and should remove them.
3) I strongly recommend anyone looking to get into girlpla to practice on some cheap gunpla first and foremost. You can absolutely get several kits for the price of a typical MD and get the practice in to make the build a success.
If you have any further questions don't hesitate to ask.