"Can someone help me with the correct way to do this?"
The correct way is to NOT do this.
Magically creating or accessing variable names is a really bad way to write code, which is explained in the MATLAB documentation, because that code will be "...less efficient and more difficult to read and debug than code that uses other functions or language constructs"
For whatever reason, some beginners imagine that dynamically creating or accessing variable names will solve all of their problems. It will not: it will actually make your code slow, buggy, hard to debug, hard to read, and pointlessly complicated:
Much simpler is to use indexing, which is trivially easy and very fast, a table, or dynamic fieldnames in a structure.
