Questions about Undergrad reserach

I will be a senior at UC Berkeley studying Computer Science, and I am looking for some research experience in the fields of CS for next fall. The CS class that I have done best in is machine learning and I also enjoy working with big data (2 internships related to it), so any type of research that is ML/data or a mix of both would be ideal for me. I have a few questions regarding the process of getting research:

  1. Because I am off campus right now, how should I go about applying to research positions? Usually, when someone sends an email to professor inquiring research, it comes with meeting a professor personally at office hours to discuss opportunities, but obviously, that wouldn't work for me right now. So what should I say in my email?
  2. How many professors should I apply to and reach out before I expect an offer? I sent out like 3 so far and gotten no responses yet. I try to read research papers and personalize my emails to them, but this is taking really slow so far, unlike when applying to jobs where I would just use almost the same cover letter and spam resumes.
  3. How much does GPA and internships matter? My technical GPA is 3.3 but I got an A in machine learning, and I'm trying to apply for positions with professors in that field.

THanks in advance!

Start with professors whom you had as an instructor. They have a better chance to know you. You might have to wait until the beginning of the academic year though since faculty are often away and busy during the summer. Bepersistent and definitely go ask them in person as soon as possible.