Two competitors in similar market spaces, sort of like Coke vs Pepsi.
In terms of deciding which one you should get, pay attention to your experience being sufficient to pass endorsement and look at job listings that resonate with you to see what certs they tend to mention. There is no universally correct answer.
Well, CompTIA is a trade association, not a cybersecurity association. CompTIA is fine as a source of vendor neutral entry level certifications until you get the experience for better ones. ISC2 is a cybersecurity certification organisation that has a reputation for respected infosec certs like the CISSP and CCSP.
Might be worth looking at https://pauljerimy.com/security-certification-roadmap/
to see where the CompTIA exams fit in.
Not sure which certification you are considering but here is a similar discussion: https://community.isc2.org/t5/CC-Study-Group/Certified-in-Cybersecurity-vs-CompTIA-Security/td-p/529...