Hoo boy. Ok. Let's try to parse this out..
Who should enter into informal preaching even for 7-10 minutes a week. Who would be qualified to do that. 40 or 50 people would be watching. It must be prepared and have good points about the scriptures.
It honestly depends on who you ask, what denomination you're a part of, and what you mean by "qualified". Some churches require you to have certain degrees of education (Bachelor's, Master's, etc.), and some just want you to be able to speak well. It just depends.
Encouraging street people to get saved and teaching them about the Lord and His Word. This is what I did, but what would you do?
I don't know. If I went back in time, I think I'd go to a very different school and study in a completely different field. If I still decided to go into foreign mission work, I think I'd choose a school or program more dedicated to that than the one I chose.
What if you don’t say much in real life,
I assume you mean, what if the person is an introvert? Then you do what you can, where you can.

Not everyone has the same gifts, and I've always felt mine was more encouraging those who are witnessing, and less going out and witnessing to strangers myself.
what if you don’t study everyday.
I don't think most people do.
It doesn't matter; do what you can! But if you're infirm, or have serious medical health issues, don't push yourself beyond your limits. It's okay to just pray, and attend church when you can.
Who of you would tackle this very important task, for a year?
Been there, done that.
Do any of you witness, or not?
I honestly don't know what you mean by that. Witness in what way? Covid's left everything kind of...limiting.
Having the Holy Spirit is a requirement and maybe all you need for some of you.
Sure.
How much knowledge does one need.
I think it's important to have a basic knowledge of what the Bible says about salvation, baptism, etc. before setting out on such a daunting task. It's important to be spiritually and knowledgably equipped. Of course, you can't plan for EVERYTHING, and sometimes even the witness of a child who doesn't understand everything can be enough. However, with adults, eventually you'll be faced with very difficult questions, and at that point, it's a good idea to tackle the hard questions together! (Also no shame in saying, "I don't know, but let's study about it together and find out!")
A certain amount of intelligence, possibly, but you don't have to exactly have a genius IQ.
Popularity doesn't matter.
Mainstream and those with the gift of gab, these gifts are helpful.
Quite so. I think. Maybe? Not sure what's meant by "Mainstream".