Don't just give up yet, KNEC provides you with excellent chances to revive your dreams and compete with your peers who made it to top colleges and universities.
Most Kenyan O-level graduates normally give up very fast and opt to accept defeat without need to think of plan B and C. This is a huge mistake that should be discouraged in the strongest terms possible.
The Kenya National Examination Council [KNEC] has in place a variety of courses they test which you should know as alternative to university placement service. What you need to do, is to identify an authentic and legitimate colleges [check kuccps website for colleges that offer TVET] that provides learning of these courses and enroll for the program of your choice.
Once you graduate for a certificate course, you can proceed to Diploma then finally pursue a degree course. It's a slow process, but its the best because you learn in a slow but practical way. Also visit KASNEB website for more courses.
Some of the KNEC courses are in the document attached below: