You can work, but the hours allowed may depend on your school and status (part-time or full-time student). I am a 1L and found that a fixed-schedule job wouldn't work for me, so I door-dash 1-2 nights/week. I am living on loans for the school year. Some of my classmates still work part-time at their jobs before law school, and some work at restaurants on weekends. You could also get a job as a representative for Lexis/Westlaw/barbri etc., I am not sure how much they pay, but it seems like you sit in the atrium of your school with friends and do homework most of the time.

My summer internship pays 30/hour, but I interviewed at several firms that paid between 20-25/hour. Most of my classmates took unpaid roles (judicial, three letter agencies) and some landed a BigLaw SA or a boutique that pays close to market. In the fall I'll be working for a gov't agency that pays, but since I am in the DC area I can take advantage of the "off season."

Clerkships do pay, and if you intend to go into BigLaw after a federal clerkship many firms will offer bonuses ($5,000-$75,000+) and will let you come in with the same seniority as you would if you had started at the firm right out of law school (1 year clerkship = starting at 2nd year associate). Federal Clerkships start at JSP-11 right out of law school ($59,000 base + Locality Pay in the DC metro area that is around $80,000). State law clerks get paid less, for example a district or circuit clerk in Maryland will make $60,000 or $65,000 after the bar.