I'm in a bit of a pickle at my first Front-end Dev Job. I was hired as a junior Frontend Developer at a start up. While other technical teams seem to be established, the Front-end team isn't. in the GUI team, We have myself and one other senior dev who is a full-stack JS dev. Our app is 99% legacy jQuery code, which I am sort of familiar with but I am more used to using react and really I am the only react FE dev here and at times it's a pain to inject react code to make it work with our old code base. So there is some frustration there. Whats more is that in my 2nd month, I am working alone on a complex react FE app, and my senior dev worked in a rush to build the BE api for it, before his 4 weeks leave. I was briefed 30 mins about the api that was presented in google docs last min before he left for his leave. (I expected to be shown a demo on PostMan or Insomnia).
I tried working with the the BE APIs and can't seem to get basics to work and it's not easy to figure without the person who made it being around,
I also think, best practices weren't followed and isn't followed in FE/BE dev processes. Everyday it kinds sucks when I can't get back-end stuff to work which should be straightforward. I can only ask other for help so much as they may be kinda familiar with FE code base but even they are generally always busy with their own work. Additionally, the app that I'm working on is in the spotlight with the senior leadership team.
I feel like in coming months I could get under the radar as someone who is not capable at work. I've never been so troubled in my previous career to stick with the work, and I really want to get a years' worth exp before I move on elsewhere.
How can I improve my situation and what are your experiences?