Completely ignoring that fucking crazy statement from the video:
Yes, it can contain meat. But you normally start somewhere at around 5months with only single types of veggies, so you can check allergies and also it’s easier for their digestion. I think you normally do not start any meat before 8 or 9 months.
Just a wild guess: are you using the 5ghz or 2.4ghz Wifi? 5ghz is way faster but very fidgety with larger distance to the router, walls in the way or other routers nearby.
So, maybe you can troubleshoot your way out:
Good luck!