My daughter went to college for 7hrs in the semester in 2021. is she considered a fulltime or p/t student? she also worked

That sounds like part time----but look at the 1098T she received if she has one---it should indicate whether she was considered to be part time or full-time.   If she was older than 18 and was only part-time then you cannot claim her as a dependent if she earned more than $4300 in 2021.

@princess3730-gma @Hal_Al @xmasbaby0 

Neither, if 7 hours total.  7 hours is not part of any 5 months of the tax year.

[quote from IRS Pub 501]

"Student defined. To qualify as a student, your child must be, during some part of each of any 5 calendar months of the year:

1.A full-time student at a school that has a regular teaching staff, course of study, and a regularly enrolled student body at the school; or

2.A student taking a full-time, on-farm training course given by a school described in (1), or by a state, county, or local government agency.

The 5 calendar months don't have to be consecutive."

She would not qualify to be a student at all.

She is probably part time, not fulltime, but probably half time or more.  Each school determines those definitions. 12 hours is usually full time and 6 hours half time. 

So you student probably meets the half time or more criteria for claiming the more generous American Opportunity Tuition Credit (AOTC)  but not the criteria for being a full time student for being your "Qualifying Child" dependent.

There are two types of dependents, "Qualifying Children"(QC) and Other ("Qualifying Relative" in IRS parlance even though they don't have to actually be related). There is no income limit for a QC but there is an age limit and Full Time student status test, a relationship test and a residence test. Only a QC qualifies a taxpayer for the Earned Income Credit. 

A person can still be a Qualifying relative dependent, if not a Qualifying Child, if he meets the 6 tests for claiming a dependent:

1. Closely Related OR live with the taxpayer ALL year
2. His/her gross taxable income for the year must be less than $4300 (2021).
3. The taxpayer must have provided more than 1/2 his support

In either case:

4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or be claiming a dependent of his own
6. He must not be the qualifying child of another taxpayer