How I can fix my drone

@hplabon79 for now do not charge or plug your drone into power. That can potentially make a bad situation worse. this is going to be tough since I suspect the motors having gotten submerged and those most likely cannot be opened. Anyhow, what I would start with is reassembling the complete drone. Most of it will be plastic etc., so it may snap together or there may be some screws. Use something like this video to work on that. Once opened and disassembled you want to clean all the parts with some high grade isopropyl alcohol. Use something like this guide iPhone Wasserschaden reparieren to clean your circuit boards etc. It was written for an iPhone but the cleaning steps can be used for your circuit boards as well.

Your motors can be submerged if they cannot be opened and you may want to use a small amount of canned air to blow those out after. As for your cameras etc, hard to say if they will survive the water damage. You can clean those with isopropyl too but you may get (residual water) stains on the lens. You must replace the Battery. At this point its a bit of a gamble but in reality you got nothing to lose. Good luck and let us know how it works out.