Hey, Alex, that’s a great question! I think that depends on a lot of factors. For me it took about a year, and for most of that time I was probably spending close to 40 hours a week studying. During that time I studied for the RHCSA and the RHCE to try to get a strong foundation in linux, and then I took a free CCNA course (did not take the exam) to try and get up to speed on networking and the OSI model. Afterwards I started going through a ton of DevOps courses on linux academy (now merged with ACloudGuru). I setup a home lab and containerized things, setup jenkins to create CI/CD pipelines, played around with kubernetes and canary deployments, and ended up getting a basic AWS certification. At this point I started applying for jobs and I hit a wall. With no experience and no degree it was pretty challenging to get past most of the HR filters, and 4 of the 5 job interviews I got all came from networking and going to meetups. I had to really sell myself and my skills at picking up new technologies quickly in order to be considered once I managed to get an interview, so this involved a lot of interview prep and spending a lot of time figuring out how to build a strong resume.
While that doesn’t directly answer your question, hopefully it gives you an idea of what the path can look like and what you will have to focus time on. If you already have some knowledge in any of these areas or if you have more or less time to put towards studying that will affect how long it takes as well. Networking and talking to others about their day to day jobs helped tremendously in shaping what I needed to learn!