how do u practice this in training mode.
Put the dummy on random block, attack it with whatever you want to hit-confirm and only attack if it hits.
Try to condition yourself to only react to yellow hit sparks and the hit sound effects.
Start with shit that is easy to confirm like Evil Ryu’s (I just assume you play him) cr.LP/LK>cr.LP>cr.MP xx Hadoken/Tatsumaki, then try to incorporate that into your game (which will take considerably longer).
Then move on to the hard shit like cr.MK xx Hadoken xx FADC xx st.HP/st.MP/cr.HK etc.
It’s easier and the process is much faster if you force yourself to use the hit-confirm every time you want to produce block pressure, whiff punish or mash out of pressure, depending on the field of application for said combo.
For example the crouching light combo can be used everytime you want to annoy someone on his wake-up or you try to mash out of pressure/punish something that has a 3+ frames punish window and the low forward combo can be used every time you try to whiff punish or you get poke someone.
You probably do some hit-confirms already without noticing. Like every time you FADC an EX Shoryuken on the second hit because the first hit got blocked, is basically a hit-confirm. Also when you LP Shoryuken a jumper and hit him with Ultra 1 afterwards is kind of a hit-confirm even though the window to confirm on that is very big.
Might help to see these new hit-confirm combos in the light of those I just mentioned, just to grasp the concept.
Wow, I never thought of putting the dummy on random block 
I gotta check that out.
James Chen did an episode about confirming
https://www.youtube.com/watch?v=SeL-XYuTnNM
The best tip is to press the buttons with the expectation that they’ll hit and then stop yourself when you notice the block.