You can use REGEXMATCH:
=IF(REGEXMATCH(A1, "sites"), 1, 0)
REGEXMATCH returns true if the first argument matches the regular expression given by the second argument. As long as the second argument has no regex special metacharacters (^ $ \ . * + ? ( ) [ ] { } |), this returns true if that argument is a substring of your string.
You can use REGEXMATCH:
=IF(REGEXMATCH(A1, "sites"), 1, 0)
REGEXMATCH returns true if the first argument matches the regular expression given by the second argument. As long as the second argument has no regex special metacharacters (^ $ \ . * + ? ( ) [ ] { } |), this returns true if that argument is a substring of your string.
If you, as Ryan Shillington suggests, want to know the number of cells within a range that has "sites" in it, you might try:
=COUNTIF(A1:A100;"*sites*")
The * acts as a wildcard notion, so it will look for a match anywhere within the cell, not just an exact match for the whole cell.
I've also done this with a cell reference instead of "sites", but then you have to add wildcard-asterixes to the text in the cell.
is there a formula to check if a cell contains certain text? - Google Docs Editors Community
Is there a if text contains vs if text exact function? Instead of =IF(C1="Store 1","Arizona" I'd like it to just look for "store" so it would find store 1, store 10, and store 25.
if statement - Google Sheets - IF cell contains certain text (or texts) then return values - Stack Overflow
IF formula with 3 values/conditions
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Concatenated values
=join(", ",query({if(or(REGEXMATCH( upper($F$10),"PIZZA"), REGEXMATCH( upper($F$10),"HOTDOG")),"FOOD",);if(or(REGEXMATCH(upper($F$10),"APPLE"),REGEXMATCH(upper($F$10),"BANANA")),"FRUIT",);if(or(REGEXMATCH(upper($F$10),"COFFEE"),REGEXMATCH(upper($F$10),"COKE")),"DRINK")}, "select * where Col1 is not null"))

List Values
=query({if(or(REGEXMATCH( upper($F$10),"PIZZA"), REGEXMATCH( upper($F$10),"HOTDOG")),"FOOD",);if(or(REGEXMATCH(upper($F$10),"APPLE"),REGEXMATCH(upper($F$10),"BANANA")),"FRUIT",);if(or(REGEXMATCH(upper($F$10),"COFFEE"),REGEXMATCH(upper($F$10),"COKE")),"DRINK")}, "select * where Col1 is not null")

try:
=TEXTJOIN(", ", 1, INDEX(IFNA(VLOOKUP(SPLIT(B10, ", "), SPLIT({
{"Pizza"; "Hotdog"}&"×Food";
{"Apple"; "Banana"}&"×Fruit";
{"Coffee"; "Coke"}&"×Drink"}, "×"), 2, 0))))
