Drag and hold the piece over the square you want to move it to before you place it down. Then you can better visualize what's going to happen. Since it's online, your opponent won't see your thinking process.
Seeing the blunder milliseconds after completing the move

I have a setting where you have to confirm your move. It mostly helps me with my misclicks but you can also visualize your move

What is happening is, you can see the position better after you have moved the piece. Imagining what the board will look like after a piece is moved can be harder than actually seeing it, which is why you have that delayed reaction. I have had that happen too and it sucks, but it is part of chess. "Board vision" is the important 2nd step in chess, after the first step of seeing everything that is right in front of you.

Before making a move you're looking for reasons to like it.
After making a move you're looking at what your opponent can do to punish it.
The trick, of course, is using this mindset before making the move. Try to make your move look as bad as possible.

I been playing for 54 yrs. It still happens to me. It's my own fault though. I was taught long ago. When you see a good move ; then look for a great one. And in classic long time period games ; there really is no excuse to blunder. I told you I been playing for 54 yrs. Well I still have not progressed past the plates we all reach. It's my own laziness. If I'd really study openings ; analyze my old games and do some end game study I know I'd be solid 1800 at least. I have went as far as one can go without serious commitment to learning the deep fundamentals that beginners can't even see. Now I know this doesn't apply to bullet games ; but even in a 3 min game one can make sure before settling in a move. Until such time haste will continue to make waste..🙂
Am I the only one who experiences this? I play a lot of 5-min/3-min blitz chess at chess.com and I often find myself considering a move for a couple seconds, checking everything and 'seeing no problem', only to make the move and immediately realize I blundered a piece or a checkmate.
What is so perplexing is the fact that before making the move, I can't see anything wrong with it, everything looks so great, but it's only milliseconds after I actually made the move that the blunder jumps to my eyes. Most of the time it doesn't even take a second before I realize the blunder.
Does this happen to a lot of you guys?
Why is the blunder invisible all those seconds I spend considering the move but then why is only immediately obvious after I just made the move (i.e. most of the time it doesn't even reach a second after the move that I see the mistake)?