A new keyboard will fix this. No shop I know will work on such a keyboard or advise other than a replacement. That said, try what you want.
Laptop keyboards run from 10 to 100 bucks and are about 2 light bulbs of effort on a 5 light bulb scale.
One other thing. TAP THE NUMLOCK KEY to see if this helps.
As the title says it, I've spilled water over my keyboard. After it happened, I turned the laptop upside down and let it sit there for not even a minute (big mistake). The laptop was still on and the keyboard worked. After watching a video, I wanted to research something and noticed the keys were garbled. As such: te3st he3llo9 ho9w2 ar4e3 yo9u7. I let it sit overnight and tried removing gunk, dust and crumbs the water may have spread using a vacuum. I think it worked, as some keys started working properly. I'm 100% sure that the keyboard is completely dry and that it started malfunctioning when the water dried.
https://gyazo.com/39f13772a6a680c2a75dfa6be978d059
These keys seem to be connected. When I press one of them, the rest appears (not always in the same order). Writing this message was a struggle.
Would a compressed air can do the job for the rest of the keys or is there corrosion or other non-removable by air gunk?
The keyboard's malfunction can sort of switch. Instead of the marked keys in the screenshot not working properly (excluding the numbers and special characters), the ones that are not marked do not function properly (t and y instead of q,w,e,r,u,i,o,p) when I lift the laptop at a 45° angle and tap its side. However, when I put it back on my desk, after some time it switches back to malfunctioning like before. I suppose that using the letters does something like spreading dust or gunk. Maybe a compressed air can will be my keyboard's saviour. Or should I give the vacuum another go before trying the compressed air can?

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