All the work study awards in my knowledge were paid directly to the students as regular paychecks. You can spend the money on whatever you want. Your pay will be at least minimum wage. Some jobs/some schools may pay more.
Your work study is a bucket containing $1800. You receive it as you earn it. If you earn less than $1800 during the school year, you lose the remainder. The employer can only pay you a maximum of $1800. If you earn it all before the end of the year, you would probably lose the job. However, I’ve seen work study jobs where, if you used up your work study award, they could switch you to just a regular student worker & you could keep working.