Please give me an easy quantitative research title, the research design, and what data analysis should I use because our first research proposal got rejected.

Research design for this will be correlational. You will be finding if there's any significant relationship between a student's social media usage to their self-esteem. This is in light of how, in today's technological age, most of us are exposed to all sorts of media content which aren't always positive. For further clarification regarding what correlational research is, I've added a link below for reading. I would also suggest using the survey method for obtaining data if you're looking for something on the easier side.

For the data analysis, you're going to tabulate your data and use the Pearson's Correlation Coefficient method (also known as t-test) to determine if there's a significant amount of association between your two variables (which are the students' time spent on social media and their self-esteem). I've also written below a link defining what Pearson-r method is for further clarification.