If you are an international student living abroad I do not believe you are eligible for Questbridge:
International students living outside the U.S. are not eligible to apply to the National College Match.. https://questbridge.zendesk.com/hc/en-us/articles/218776877-Can-I-apply-to-the-National-College-Match-if-I-am-not-a-U-S-Citizen-or-Permanent-Resident-
I would also caution you against applying to over 20 schools. Beside the common app essay, each school will have their own individual essays. Some schools can have three or more school specific essays. Sometimes there will be even more for honors college programs and merit awards. My D applied to 8 schools and wrote 19 essays. Don’t underestimate the time it will take to craft a well written essay. Schools want to see that you match with them not just academically but also will fit into their unique community.
I’d encourage you to apply to the small number of schools that meet demonstrated need for international students and then do a deeper dive to narrow down the list. Have safety schools in your home country.
Look at the mission and vision statements for each school you are considering. Read the student newspapers. Research what is happening at those schools in your intended major.