A wellness visit and a physical are somewhat similar.
However at a physical the physical is much more intense and extensive than a wellness visit.
The wellness visit is just a simple checkup to see how you're doing health wise while the physical can include more tests.
You may get blood work done, check your heart and much more.
While at a wellness visit you might have your blood pressure checked, your blood might be drawn, your heart will be checked with a stethoscope etc.
The annual wellness checkup is just to see how health you are.
But a physical includes more extensive testing especially for applying for health insurance, a job etc.