In a startup, cloud engineers often take on many different tasks since there aren't as many resources available. They might work on designing, setting up, and taking care of different cloud services. In bigger companies, the role is more focused, concentrating on particular cloud technologies or platforms. They work as part of established teams, paying extra attention to making things big, safe, and well-connected in complex setups.
If you are interested to know more about it and pursue a career in this field, then I would suggest you check out this video about Deebak Kumar and how he got a job as a Cloud Engineer just after completing Advanced Certification in DevOps & Cloud Computing from Intellipaat.