What are my chances of getting into UCR, UCSC, UCI, UCM with a 2.9/3.0 GPA unweighted

What is your UC weighted capped GPA?

Calculate with https://rogerhub.com/gpa-calculator-uc/ .

It needs to be at least 3.0 for California residents (3.4 for non residents) to be eligible for UC admission.

However, if your recalculated GPA is in the 3.00-3.39 range, you should consider UCM a high match at best, and the others reaches. CS will be a more competitive major as well. Past admission rates by GPA: http://talk.collegeconfidential.com/university-california-general/2174563-2019-uc-freshman-admit-rates-updated.html