If we give a rough estimate of 5 lbs. per animal (probably a lot less than that) that's around 60 billion animals killed last year so we can eat them.
It's estimated we can add another 40% to that as unwanted by-catch. So now we have 84 billion sea creatures killed each year on purpose.
If you're concerned about the environment you might consider not adding to this number.
https://www.yourfishguide.com/how-many-fish-do-we-eat-a-year...
https://oceana.org/sites/default/files/Bycatch_Report_FINAL....