It is actually Mega-base pairs, not megabytes. But yes, that how we count it in genomics. Kb, Mb, Gb, etc.

The library type here probably refers to gDNA, mRNA, total RNA, etc. Due to biological and chemical reasons, these affect how the sequencing work and the amount of material available for the sequencer to read.

That said, this is pretty much a toy. You pay $1000 for the sequencer. You also need a $2000 PC to analyze the data. You also pay like $800 per run. So the running cost is so high it isn't worth it.