Is it always clear which part of a chromosome came from the father or mother?

Are the following statements correct?

0. We have 46 chromosomes in 23 pairs.

1. for all the 23 pairs there is always one part originating from the mother and one from the father

2. for all the 23 pairs, it is always clear, which one came from the mother or father (by position/shape/size/….)

3. Although 2 is true, in NGS (Next Generation Sequencing) it is not clear anymore from which chromosome (or chromosome part) a read fragment came from as all the DNA was put into one pot, then PCR’d and then fragmented