The purpose of the study is to learn more about whether adding onvansertib to standard treatment of FOLFIRI (Folinic Acid, fluorouracil, and irinotecan) or FOLFOX (Fluoropyrimidine and oxaliplatin) and bevacizumab will improve results in untreated metastatic colorectal cancer with a KRAS or NRAS mutation.If you decide to take part in this study, and are deemed eligible to participate, you will get randomized to one of 6 arms which are as follows:The study drug at a lower dose level + FOLFOX + bevacizumabThe study drug at a lower dose level + FOLFIRI + bevacizumabThe study drug at a higher dose level + FOLFOX + bevacizumabThe study drug at a higher dose level + FOLFIRI + bevacizumabFOLFOX + BevacizumabFOLFIRI + Bevacizumab You will have an equal chance of being placed in each arm.