CCNA

It depends on where you wish to see yourself after the course, I mean the career path you are interested in and which one you'd like to specialize?. It can also be a personal decision. Streams available are
CCNA Routing and Switching
CCNA Data Center
CCNA Security
CCNA Service Provider
CCNA Service Provider Operations
CCNA Video
CCNA Voice
CCNA Wireless?
and of course CCNA Cloud
CCNA Routing and Switching is the pathway to start learning and earn other certificates. CCNA(Routing and Switching) is a basic certification, which is started by everyone as Cisco have some requirements to be completed called as prerequisties. CCNA Cloud certification is a job role focused certification and training program that helps Cloud engineers, Cloud Administrators, and Network Engineers to develop, advance, and validate their cloud skill set, and enables them to help their IT organization meet changing business demands from technology transitions. With a CCNA Cloud certification, you will obtain the skills to perform entry-level provisioning and support of Cisco cloud solutions.

Dear student,
CCNA/CCNP/CCIE all the above courses deal with in one term "computer- networking" in LAN/VLAN/WAN scenario. CC implies cisco certified . CISCO a global major and giant player in networking devices manufacturing(HUB, SWITCH,ROUTER FIREWALL etc etc.) started this certification courses for smooth maintenance of the networks of enterprises using their devices and s/w. CCNA is for installation and mtce of small and medium size n/w and for large and complex n/w it is CCNP and CCIE which are helpful to install and maintain it. In OSI architecture layer 1, layer 2 and layer 3 is covered in depth in the said certification courses. Hope this can serve you to develop a basic idea of the courses.
Best wishes.