Q. What is the difference between the magnetic field around a straight current carrying wire and a current carrying loop.

Dear Student ,
There is no difference except their magnitude and the geometrical shape , the magnetic field is produced is same in both cases .
When the magnetic field is produced by the straight current carrying wire it becomes = $\frac{{\mu }_{0}I}{2\pi r}$
and the magnetic field produced by the circular loop =$\frac{{\mu }_{0}I}{2r}$
Hope this helps you .
Regards