What is the difference between "one bit" and "a bit"?

Is "from then on" and "from now on" the same? Is it okay to understand "from then on" as an expression changed from "from now on"?

"From then on" has the same meaning as "from now on", but uses a different tense. "From then on" refers to an event or a time that took place in the past and happened from that time on, or has continued on into the present. "From now on" indicates the present tense of an event that takes place currently and will continue to be that way in the future. Ex: I ordered the beef noodles but I think I like the chicken noodles better. From now on, I'll only order the chicken. Ex: When he was five years old he was bitten by a dog. From then on, he has always a little bit afraid of dogs.

Since it all happens in present, wouldn't it be more appropriate to say "passing by"?

Yes, since the video is showing the action occurring in the present moment, it would be appropriate to say "passing by" here. However, since this is an account of a past action even though the video shows it as though it occurs in the present, it is OK to use the past tense form "passed".

Does the word "makeshift" refer to something temporary? Are there any other alternative words to replace?

Yes, that’s correct. “Makeshift” here does mean “temporary.” You can also use the terms “provisional” or “emergency” here. Ex: The camp was full of thousands of provisional refugee tents. Ex: The tent suddenly had a hole, so the campers had to make an emergency cave.

Is “duh” a common exclamation?

"Duh" was more common in the early 2000s, but now is only used sarcastically because it is considered somewhat rude to say. Right now, young people (mostly teenagers) only use "duh" when the person they are speaking to clearly knows they are joking. "Duh" should not be used in formal situations. Ex: Of course I am the coolest person ever. Duh! Ex: Duh my favorite color is black! Can't you see that everything I own is black?

What do you normally write in the "skill/interests" section?

The skills and interests section in your resume basically relates to your professional skills and interests! For example, if you are a computer programmer, you can list the programming languages you are familiar with, the types of programming you can do, and the types of associations or clubs you are a part of. It's also a chance to list your personal interests too! Some companies like to see the types of hobbies or personal interests you have, to see if you are a good fit with their company culture. Ex: Marketing resume - marketing, communications, design, and project management skills. Ex: Business analyst resume - data analysis, statistics, business management, and accounting skills.