I have published several articels in NLM cataloged journals, of which it seems that they can be submitted via author manuscript submission. Though it appears that only NIH funded manuscripts may be published?
https://www.ncbi.nlm.nih.gov/pmc/about/authorms/#:~:text=The%20policies%20of%20these%20organizations,of%20the%20PMC%20International%20Network).
If I did not have funding for my articles, is there a way to submit my NLM cataloged submission to get a PMC on PubMed?