Security Engineer is pretty broad ranging from people write code and develop security tools and products to people just deploying firewall and security solutions.
I suppose the latter will fit you better. From how I see, you need to have proper understanding of networking since a lot of security solutions and products have to be integrated into the network. Then you need to understand what are the security solutions out there like Firewall, Proxy Server, IPS, VPN, WAF, SIEM, EDR, AV, Patch Management systems etc.
I would recommend going for generic security certification such as Security+, SSCP or CISSP to give you some theoretical knowledge of security and where those products sit. Hopefully you can your foot into the door.
I won't recommend taking product based certs since if you are working for a company, the company would normally send you go training because you will be working with whatever products the company is working.