Will interviewing people outside a pool supply store in the suburbs give a random sample

It would depend on the interview questions. If the questions were about which pets they own, then maybe. If you were asking them about which pool supply store was the best, then probably not.

No, Because there is only the people who live in the suburbs and who shop at this particular pool shop will be interviewed. This is an example of Specific Real Area Biased. For example, a survey of high school students to measure teenage use of illegal drugs will be a biased sample because it does not include home-schooled students or dropouts.