There's an issue with my ti 84 plus ce, i think i may have dropped water on it or it got a virus in it and for some reason it does not switch on, when i try to connect it to my laptop it has no reaction, when i charge it, it give and extremely dim screen. Any ideas on what to do, buying a new calculator is out of the question

Remove the battery IMMEDIATELY. Never try to power on a device with suspected water damage. If you're lucky, maybe the components aren't already shorted.

Disassemble the calculator. You can follow the guide I made on ifixit here: https://www.ifixit.com/Teardown/TI-84+Plus+CE+Teardown/118886
You'll also need to break the melted plastic holding the motherboard in.

Once the motherboard is completely removed, inspect it for any water damage (I.e. Water on the board or corrosion).

If there's corrosion then provide a picture of the corrosion so we can judge how difficult the repair will be. Baking soda is often recommended for cleaning water corrosion. I'd recommend looking up a tutorial for the exact mixture.

Once all the visible corrosion is gone, wipe (or submerge) the entire board with isopropyl alcohol. That will dispel any water that's clinging to the board. Let it dry for a few hours.

Do a visual check for any broken components or broken traces. If there was no corrosion then you can reassemble the calculator and put the battery back in. If it turns on then great! You're probably set. Otherwise remove the battery again and let us know if you're having the same issue.

You can rule out the virus, that's not a concern with the TI-84 Plus CE.

If you end up needing a new calculator, unless you need specifically the TI-84 Plus CE, you can get a used, regular TI-84 Plus for a fraction of the price.