The sequence after e f h I s is not standard or clear. Additional context or information is needed to determine the pattern or next item in the sequence.
fished
shelf
,fa,d,e,d,e,f,g,h,a,d,e,f,d,c,c,d,f,e,s,a
About 138.
E
k comes next, and then l.
S
Capital letters that have parallel lines include "H," "I," and "E." These letters have horizontal lines that are parallel to each other. The letter "H" has two parallel horizontal lines, the letter "I" has one, and the letter "E" has three parallel lines.
health and safety
T because o is 1, t t f f s s e n is two three four five six seven eight nine.
S
You can spell many, many, many words with those letters.