A+ to learn the inner working of computer systems. Network+ to get basic networking concepts. Sec+ to get basic cybersecurity concepts. All three regarded as the holy trinity of basic computer/IT certifications.
If you’re interested in joining the IT industry, that’s a good start.
when you determine what or If you’d like a specialty you can go down servers (VMware, Red Hat, Microsoft Cloud), networking (Cisco), cybersecurity (Sec+/CISSP/CISM/CASP/OCSP), project management (Project+, PMP/CAPM)…then there is programming or database management.
I can’t even imagine what the journey will hold for you but wish you well. You’re going to have to grind.
There are practice tests. There are YouTube videos.CBT like ITProTV, CBT Nuggets, INE, Pluralsight, etc. O’Reilly Books. Labs….if you get a server to do virtualization or a decent laptop with Virtual Box or VMware player/Pro.