Cheat Engine

[SlipknotSL]

Personal sorry my English writing, I am using a translator.
I come to ask how to convert 4 bytes to BYTE.

[atom0s]

BYTE (if you are referring to C/C++) is defined as 'unsigned char', which is 1 byte. If you are truncating the value, just index the first byte you have.

If you are converting a 4 byte type to a byte, cast it like:
unsigned char data = (unsigned char)oldData;

[SlipknotSL]

and VB.NET?

[atom0s]

Use the Convert class in .NET to convert values back and forth. As well as the BitConverter class.