I was changing the battery to my 1994 Honda accord and I accidentally put the positive on the negative and negative to positive. It's sparked at first but it stopped, but when I went to start it it did nothing. I thought the wires may have been a little loose so when I went to tighten them that's when I noticed my mistake. So what happens in that scenario did I burn something out or shorted out a fuse? I can't find anything

I was changing the battery to my 1994 Honda accord and I accidentally put the positive on the negative and negative to positive. It's sparked at first but it stopped, but when I went to start it it did nothing. I thought the wires may have been a little loose so when I went to tighten them that's when I noticed my mistake. So what happens in that scenario did I burn something out or shorted out a fuse? I can't find anythingMight have fried the ECU... are you getting any codes off it?

I don't understand? I'm not getting any lights on the dash if that's what you mean. The head lights come on and the horn works, also my hazards come on but that's it. When I turn the key it does nothing

Might have fried the ECU....are you getting any codes off it?

None of the dash lights are coming on only the head lights horn and hazards work. What is the ecu? And thanks for your time

Look in your fuse box for fried fuses.

Test all under hood and under dash fuses with a test light or multimeter.

I would say fuses as well, The starter doesn't need ECU to crank.
A test light will follow power from battery to starter and to ignition switch and to starter.
When you find the Fuse? I would check that it is still charging.

You'll likely find the Engine Control Unit (ECU) has suffered damage. Delicate electronics don't like that kind of reverse power surges applied to them.