Seeking Information Formula for specific logic

Something like this:

=IF(OR(G2={"T50","T51","T52","T53","T54","T55","T56","T57","T58","T59"}),"V",IF(G2="T67","S",IF(G2=T99,"L",IF(G2=T60,""))))

If you have multiple possibilities.. then enclose your first structure with the { } brackets as you did, in an OR() statement.

The above formula is a working formula, but obviously you need to add some other elements.

Note that you can only have 7 nested functions... If you exceed that, then you will possibly need another function or incorporate the use of a side table that lists the possibilities and the desired output in adjacent column, then use a Vlookup() function... e.g. =Vlookup(G2,X1:Z100,2,FALSE) where X1:Z100 is where the table is located.

Another possibility is the Choose() function...

e.g. =CHOOSE(RIGHT(G2,2)-49,"V","V","V","V","T","T")

where you can have up to 29 values to choose from. The Right(G2,2) extract the 2 digits from G2 and subtracts 49, to get a number starting at 1 (that is what Choose function needs. So if result is 1, it retrieves the first value from the list after the condition).