Is reforming and isomerization the same thing?
TL;DR: Isomerization is a subpart of reforming process. There are four major reforming reactions. Isomerization is one of them.

Reforming is a processing technique by which the molecular structure of a hydrocarbon is rearranged to alter its properties. The process is frequently applied to low-quality gasoline stocks to improve their octane number and thereby improving combustion.
There are four major types of reforming process:

Dehydrogenation of naphthenes



Dehydrogenation and aromatization of paraffins to aromatics (dehydrocyclization)



Hydrocracking of paraffins



Isomerization of normal paraffins to isoparaffins


You can see that during all the process except isomerization, there is a loss of atoms either carbon or hydrogen. However, there is no change of atoms during isomerization process.