Newer Excel (Microsoft 365 and Excel 2024) has functions that cut text at a delimiter directly, with no FIND arithmetic:
=TEXTBEFORE(text, delimiter, [instance_num]): everything before the delimiter. TEXTBEFORE(A2,"@") is the user part of an email.=TEXTAFTER(text, delimiter, [instance_num]): everything after it. A negative instance_num counts from the end: TEXTAFTER(A2,"-",-1) is the part after the last dash.=TEXTSPLIT(text, col_delimiter) splits the text into several cells that spill to the right.
If the delimiter isn't found, TEXTBEFORE and TEXTAFTER return #N/A. Their optional if_not_found argument (the 6th) gives a value to use instead.