(English is not my native, so sorry for my mistakes bellow and above.

A tinny bit of background first: I am a 27yo guy who, by profession, is a telecommunication engineer.

I have been working since I was 19-20 yo, but never in the field of telecommunications or networking. I have actually been in one company only for all this time, working as a tech support along with million different things. It seemed like a great opportunity back then, with a good combination of work, location, etc.

I kinda am getting more and more sick of it, as years go by. I feel like 2023-2024 is the time to switch jobs and go try something else. Now with that being said, I would really like to go back into telecommunications/networking and work in that field for the first time. As far as I know, it is quite hard getting a good networking engineer in my country, so I should probably have a chance of landing a job in that area with some knowledge.

One problem is that since I didn't work in that area, I kinda forgot everything that we learned at college. I used to know decent amount of stuff, I understood how things work and so on…Now I don't have much clue about it.

What would be the best way to get that knowledge again and possibly upgrade it, so that I would be able to work in that area?

I was thinking of buying some Udemy courses for Cisco CCNA to relearn stuff. Maybe not go for certification right away (or at all)…but that should still help?

Can anyone possibly recommends me some good Udemy classes or possibly some other web page that I could go to learn? Or maybe a youtube channel or anything really that would help wit my learning.

I was also checking on some Cisco CCNA kits on Ebay. Should I buy some of that? Will that help me with learning? They don't seem to be too expensive..I could probably afford it, if it would help me.

Any other suggestions are welcome