For genomic feature extraction I recommend AGAT or gffread:

1. https://agat.readthedocs.io/en/latest/tools/agat_sp_extract_sequences.html

2. https://github.com/gpertea/gffread

you should be more specific as to what you are trying to do.

in general parsing a GFF file, while error prone and annoying it is reasonably straightforward,

look at your file with a text editor and identity what steps are you trying to achieve aka which field of which region should be extracted into what foramt