Can I be claimed as a dependent? I started working full time on July 17, made roughly $31,000 since, but my parents provided my fully support from Jan 1-July 17.

If you were a full time student for at least 5 months, and under age 24, that satisfies one of the tests.

Do you still live at home?  Or did you live at home more than half the year?  That's the second test.

Did you provide more than half your total support for the whole year?  That's the third test.  Your total support is the value of housing, food, entertainment, medical, travel, clothing, etc.  If you live at home, your parents are counted as providing support equal to a percentage of their rent, food, utilities and other household expenses (such as, if there are 5 people living in the house, 1/5 of their housing cost counts as support provided to you.). Then, even if you earn money, it doesn't count as support unless you spend it on your own support needs.  For example, if you saved your earnings, or spent it to support your romantic partner or your child, then it doesn't count as support you provided to yourself.  There is a worksheet to help figure support in publication 501.

https://www.irs.gov/forms-pubs/about-publication-501