Assuming the data is in column A, starting at A2, then in B2 enter formula:
=IF(ISNUMBER(SEARCH("Min",A2)),LEFT(A2,SEARCH("Min",A2)-1)*60+SUBSTITUTE(MID(A2,SEARCH("Min",A2)+4,255),"Secs","")&" Secs",A2)
copied down.
You can then copy and paste special >> Values over the original if desired and remove the formula column.
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