CompTIA A+
My transtion from Accounting to IT all started with this simple entry level certification. The A+ taught me the fudamentles of IT from Hardware, Software, Netw0rking and Cybersecurity. Personally I would say the A+ is one of the best certfications i have got, not only did it prepare me for my career change, but it taught me broad range of topics within IT. This is a certification that I would reccomend to anyone both beginners and seasoned IT professionals.
CompTIA Network +
This certificati0n was the bane of my existence at one point :). Understanding Networking can be challenging due to the techincial complexity of topics and wide variety of technologies. The Network + is a good cert to undertand the basics of networking. If you are serious about networking, there are better certs such as the CCNA.
CompTIA Security +
The security is a well known CompTIA certification that teaches you the fundemntals of security within the IT space. The course was not as technical as the other two certs but it does focus on security operations and oversight. Perasonally, this cert was the easiest out of the trifecta
Core 1:
Core 1 mostly focuses on the hardware aspect a worstation, printers, and infrastructure within IT
Core 2:
Core 2 focuses more on software/ Operating sytem fundimentals-specfically windows OS
Study Material: CompTIA A+, Network +, Security + COURSE MATERIAL
Professor Messer:
1)Practice exams on through his personal website
2) Udemy Cources
3) Messer Youtube channel
Jason Dion:
1) Practice exams on Udemy
2) Udemy courses
Mike Meyers:
1) All in one A+ exam book
2) All in one Network + exam book
3) All in one Security + exam book