Hi Ganga , hope you are doing well. According to your question I want to mention that with a rank of 5800 in KEAM and matching it against rank vs cutoff trends from previous years you have minimum chances of securing a seat in CSE in any Government College. However there are 3 private colleges still available  that will accept you for their CSE course. I am mentioning the name of those 3 institutions alongwith the last rank that got admission the previous year, below:-

• SCMS School of Engg. & Tech., Ernakulam- 11512
• Toc H Institute of Science & Tech., Mulamthurutthy - 16614
• Viswajyothi College of Engg. & Technology,Vazhakulam -11716

Hope this helps

Thanking you

Yours sincerely

Somenath Chattopadhyay