Dear Chinedu Onyeke

you'll find most of your questions answered here:

https://www.nist.gov/pml/sensor-science/what-synchrotron-radiation

There you'll find information about e.g. vertical and horizontal angular distributions, energies of the emitted light, etc. In general, these properties do not only depend on the energy of the electron, but also on the magnetic field and the periodicity of the magnetic devices (bending magnet, wiggler, undulator).

Another very helpful resource for beginners is the X-ray data booklet https://xdb.lbl.gov/

in particular section 2, https://xdb.lbl.gov/Section2/Sec_2-1.html

But - at more than 1 GeV energy, electrons ae travelling at more or less the speed of light in general.

Good luck, Dirk