There are dozens of local Amateur Radio Clubs in the DFW area. The list below is not exhaustive, but represents most of the region. Meeting and testing times are subject to change, so verify with the clubs themselves before going.
Tarrant, Johnson & Parker Counties
The Cowtown club handles almost all of Tarrant County.
https://www.cowtownarc.org/get-your-license
They have license exams on the 2nd and 4th Thursday at 7PM.
K5SKLD is the club here in Arlington.
http://k5sld.com/license.shtml
They have license exams on the 1st and 3rd Saturdays at 10:00am.
WA5JRS is the Mansfield club.
https://www.mjars.org/training
They meet on the 1st Friday at 7PM.
Testing has to be arranged ahead of time.
They also offer training/licensure classes that span multiple Saturdays. Contact the club for information.
W5JCR is the Johnson County club and is based in Cleburne.
https://www.w5jcr.com/training/
They meet on the 2nd Saturday at 7PM.
Testing has to be arranged ahead of time.
W5PC is the Parker County club.
https://w5pc.org/ham-license-testing/
They meet on the 2nd Tuesday at 7PM.
Testing is on the 3rd Monday at 6:30 PM.
Denton, Collin & Dallas Counties
DCARA handles most of Denton County.
https://dcara.net/ham-license-testing-and-classes/
They meet on the 4th Monday of each month at 7 PM.
McKinney has its own club separate from the Collin County group.
https://mckinneyarc.org/marc-ve-group/
They meet on the 3rd Sunday at 2PM.
Plano also keeps theirs separate from the Collin County group.
https://k5prk.net/ve-testing/
They test on the 3rd Monday at 6 PM before the 7PM Meeting.
DARC handles North Dallas.
https://w5fc.org/club-activities/how-to-get-a-ham-radio-license/
They are a large club that meets on the 1st Tuesday at 7PM.
Testing has to be scheduled ahead of time.
Ellis, Kaufman & Van Zandt Counties
WD5DDH is the Ellis County club.
https://www.wd5ddh.org/index.php/home/testing-and-licensing
They meet on the 3rd Thursday at 7PM.
Testing is hosted periodically.
K5CCL is the Cedar Creek Lake area club.
https://k5ccl.wordpress.com/
They meet on the 2nd Saturday at 10AM.
Testing has to be scheduled ahead of time.
K5RKW is the Rockwall club.
https://sites.google.com/site/rarck5rkw/home
They meet on the 3rd Tuesday at 7PM.