This is a very broad question. As you know, computers are now part of every aspect of our lives .. so you've got LOTS of options.
First, hardware. You can be a technician and build / repair PCs for a living. You can do this for individuals (not much money there, but you are your own boss), or you can do it for a company as the 'IT guy' (hourly pay, not enough to support a family, but stable and relatively secure).
This kind of work requires basic PC knowledge and the relevant certifications (A+, for instance) will help land your first job. Once you have experience, that will count more than the certs.
In the same vein, you could specialise in a more advanced form of hardware. Networking, for instance, requires people who know how to route, splice, and set up cable runs, set up PCs on the network, etc. There are many specialised networking certifications that can lead you on this parth: Cisco, Network+, etc.. Choose the easiest / cheapest and if you like it, you can go onward.
Pay in the Networking field can vary from slightly more than a PC tech (for laying cable and setting up PCs) to executive-level salaries in the 6 figure rance for those who get their Cisco certs, lead a team of network engineers and (generally) have a degree and the knowledge to design large networks.
Finally, the hardware category also includes Computer Engineering. This field specialises in designing and building new technologies. Want to work with Intel or AMD and design new CPUs? Work with nVidia to design new GPUs? Fujitsu to design new hard drives? If so, this is your field. The minimum entry price is a Bachelor's degree in Engineering (Electrical or Computer Eng are best). Pay is professional-level salary.
The other side of the coin, of course, is software.
The 'technician' level of software employment is similar to hardware. These are the guys who install OSes and other software on PCs for others, who troubleshoot software problems, etc.. Again, the price of entry tends to be a certification (Microsoft certs are particularly useful since most professional environments are MS based) and an hourly wage is most common.
Software, of course, must also be written and tested. Doing this generally requires a degree in Computer Science. If you enjoy writing code and solving math problems, then you should looking into programming.
There is far more to software development than writing code, though. Someone needs to design the software (aka, software architecture), someone has to test it thoroughly (QA testing), etc. etc..
If this hasn't helped you narrow it down, then consider getting entry-level jobs in the various areas of the industry and see what really appeals to you. Get a job in a PC shop and learn to build and test systems; get a job as a tech-support guy and learn how NOT to throttle your co-workers. These will help you decide how to spend your life.
For instance, 15 years ago, I thought that building PCs was the greatest fun in the world. Now, I slap new parts into my aging machine as I need them .. the joy of slotting a new card into an old slot just doesn't do it for me anymore.
(that's what SHE said!).