Your question would be easier to answer if you were to share something about your programming background, and your objectives. e.g. how experienced are you, which languages do you use already, if any, and what do you want to do (get a job, build a particular thing, build multiple CRUD sites, ...)
I just got out of my degree and have the exact same problem. I was thinking in getting a full-time RoR + react job because that's what many startups are using. However, I don't know the exact reasons they use it besides the large community. It's hard to make a framework choice without knowing what are the parameters to be considered when you have zero experience.
A) Which web framework (e.g. Rails, Django, ...) should I spend time learning on my own, because it will help me get my first job after my degree?
B) Which full web stacks, including front-end (e.g. React or Angular) and back-end (e.g. Rails or Django) are popular among my potential employers, and why?
Is it A or B, or something else?
Also:
- What is your level of experience in programming? Zero? Some projects as a minor during your degree? Several years writing your own pet projects?
- What language(s) do you already use?
In choosing a framework to learn, you're not making a lifelong commitment. If you intend to be a professional developer for the next 40 years, I doubt you'll use the same framework or type of language for the whole time.
The most important thing is to pick something which allows you to be productive early on. That will help provide motivation to keep at it, to learn more, and to get better.
If you are starting out, then trying to learn Rails and React at the same time seems like a steep path. Unless you have a lot of concentrated time, you might be better off learning one at a time. If you pick React first, then build a React app that consumes some existing APIs. If you pick Rails first, then build server-rendered sites first. Then learn to present the same content via APIs. Then add React.