Hardware & Networking

Training and on-the-job experience are the only ways to become a network admin. Here are some steps:
Learn about how network protocols help to make a network work properly. L1, L2, L3 and L4.
Ethernet - L2 routing, ARP, STP, etc. IP - L3 routing, RIP, OSPF, etc. TCP/UDP - How packets are built and interact with the network. You would then learn vendor-specific tools/commands to make a network work and route packets correctly. At the end of the day, all networks work the same way, the only difference is what commands specific hardware required to make them work. I would also look into how network services like DNS, DHCP, PXE, etc. Work so you will be able to better troubleshoot issues. * To become a sysadmin you have to do following courses.
1- You should complete your graduation
2- Do A+ hardware course (basics in hardware)
3- Do MCITP course (Microsoft Windows)
4- Now you can find a job in sysadmin easily.
5- If you want a higher course you can go for CCNA, CCNP and security courses.

If you want to pursue a career in networking then there are two ways to do it:
1. Do specialization in computer networking by doing PG from IISc, IIT, NIT, etc. After completing PG, you will get a chance to work with networking giants like Cisco, Orange, Juniper, etc. Here you can get a chance to work in their R&D department. (Here you work as a researcher).
2. Another way is that you can enter into this field by obtaining vendor certifications like CCNA, CCNP, CCIE (Cisco track) or JNCIA, JNCIP, JNCIE (Juniper track), etc. By following this certification track, you will be able to design, install, configure and troubleshoot small to the large-sized network. This is also a good choice to enter in the networking field. (Most people follow this).
Now, the choice is yours, whether you want to become a researcher in networking field or to become a network professional.
Both ways are good. Ask yourself and decide which path to follow.