Having interest in Machine Learning I looked through quite a few posts in the relevant subreddit a bit back and a lot of people in the industry were saying a masters is highly recommended and people usually end up moving into the position at the start within a single company rather than applying for ML engineer and getting directly hired in from the outside right out of college. Are you looking more into research and development or application? The former will require a lot more math I imagine, but I cant really give much more info on either of them because I just don’t know.
It can change, as you saw me nudge it as well during training. They are just optional as in you can choose to not include them and operate only with weights. The times you would not want to have biases is a bit complicated, but they exist. But the standard networks in place today all have weights that I know of. There are weightless networks as well iirc but they require a ton of memory and I don’t really know anything about them lol.