Replace characters, and find a position
SUBSTITUTE replaces every copy of a piece of text with something else. It works on content, not position: =SUBSTITUTE(A2,".","-") turns every dot into a dash wherever they happen to be.
FIND answers the other question: where is it? It returns a position number, counting from 1, and #VALUE! when the thing is not there at all. On its own that is mildly interesting; combined with MID or LEFT it is how you split text whose parts are not a fixed width.
FIND is case-sensitive. SEARCH is the same function without that fussiness, and it accepts wildcards.
In B2, replace the dots in the phone number with dashes, then fill down to B4. In E2, find the position of the @ sign in the email address in D2.
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