I don't think you need the certs but there are some books, and studies you should undertake.
1. Database Design for Mere Mortals ... Probably one of the bests books on the how's and why's of the RDBMS. In Cod we Trust!
2. CCNA. I don't think you need the cert, but you should understand networking.
3. LDAP, DNS, SSL... These three things are kissing cousins but few people know the history or understand the tooling here. Setting up OpenLdap, Bind and your own SSL server is something you should do ONCE...
4. Containers and Hypervisors... There is more to life than Docker. I would make the argument that docker as its used is harmful to software development. Spend some time with VM's and LCX... Learn why you would want to use each, and where Docker can be a source of collisions.
5. Hardware: Find something that interests you and go deep. Have a clean switch/network setup at home. Build something with microcontrollers or at least write software for them (esp32). Pick up 3da printing as a hobby. Revive legacy hardware. There's a million things you can do here... The important thing is that your hands are on things other than the keyboard to get it done!
6. BSD: Do you need to run a pure BSD install and work with it, no. But there are plenty of NAS, ROUTER and other apliance systems that use it where you can dabble. OpnSense is an amazing product and you can stick your toe in with that, and hone those networking skills!
If you're not the self directed learning type then all of the above might not get you going... Find a non profit that needs a nerd and do a project involving any of the above for them. As a bonus, if you ask nicely they will write off your time as an unkind donation that has tax advantages (at least in the US).
