1 - follow the directions of pinned post in this forum about posting OBS Studio log when asking for help (link in my .sig)
2. OBS Studio is powerful, and somewhat complex, software, so spending time to learn how it works is pretty much needed (unless you have someone really knowledgeable in OBS Studio who is available and willing to handhold you through setup and operations). There are lots of YouTube videos, however, there can be more noise than signal as often important context and implications aren't mentioned. So, I much prefer reading properly written and edited guides. Fortunately there are now such (free) eBooks for OBS Studio that I've come across -
https://streamgeeks.us/ Online Resources
also, a sometimes helpful utility depending on your specific setup
https://streamgeeks.us/fix-audio-sync-issue-in-obs/
As for your post - your comment about modem and proximity makes me think you are using WiFi, right? for testing, use an Ethernet cable (if need be, USB 1GbE adapters and room length Ethernet cables are relatively cheap. Unless you have sophisticated real-time WiFi (RF) monitoring capabilities and know how to use such (almost no regular consumer does), then you coudl spend a lot of time dealing with a WiFi jitter/latency/contention issues (or, might have nothing to do with your issues)
real-time video encoding is VERY computationally demanding. Modern mobile device have built-in circuitry to enable such. Whether your PC has such, and is properly configured (OS, drivers, OBS Studio config, etc) to make efficient use of hardware not known without OBS Studio log. So first is making sure PC adequate to the task (and optimized if under-powered), then quality of Internet connection (if using WiFi in a dense urban area, then bound to have challenges), then OBS Studio settings/config and your source setups
I stream 1080p30 at 7000 kbps (note, upper / lower case K (and M's) has significant meaning (8X) .. be careful capitalization) which is a bit overkill, but good to have for folks watching on large screen TV (complete bandwidth overkill for mobile phone viewership)
As for 'zoomed in'- that is your Video source (presumably, and whether/how you cropped that Source or not). Any number of reasons for what you are seeing... not really practical to comment without knowing camera resolution, how connected to PC and OBS Studio, OS settings for device, OBS Studio Video Source & canvas settings, and more
