how do the three block letters differ in pronunciation?

Question

SET 1:
sTage
Take
Dig

SET 2:
sKate
Keep
Gate

SET 3:
Pen
sPend
Bend

sorry, the question should be changed as
"how do the three block letters differ in pronunciation IN EACH SET RESPECTIVELY?"

Answer 1

sTage: The "t" in "Take" touches the roof of your mouth, since this is an "st" sound, you first make an "s" sound and then a "t" sound, and the tongue doesn't quite touch the roof of the mouth.
Take
Dig

SET 2:
sKate: The "s" is pronounced and then the "k", the tongue goes up and then down
Keep: The tongue says in level to make the "k" sound.
Gate

SET 3:
Pen
sPend: The "P" in Pen has a puff of are as you say it, the P in spend does not do that, just like the word "spot"
Bend

Answer 2

D is a 'softer' form of T
G is a softer form of K
B is a softer form of P

Actually in the Welsh language there are words that normally begin with T, C, P which in certain circumstances 'mutate' or 'are softened' to d, g, b

Answer 3

t k and p are voiceless stops
d g and b are voiced stops

p and b are bilabial stops
t and d are alveolar stops
k and g are velar stops

the voiceless stops at the beginning of the words are aspirated, the voiceless stops preceded by "s" are not aspirated