Hi @mauropingarelli
''The impurities in the juice causes corrosion and provides circuit paths for the electricity which were not in the laptop's operating design and could damage the components. The corrosion starts immediately and is ongoing until it is completely cleaned away''
''First ***do not try to charge or to turn on your laptop*** and then ***disconnect or remove the battery as soon as possible*** from the laptop'' minimize any further damage.
Then you need to dis-assemble the rest of the laptop and clean ''all the affected parts'' using ***Isopropyl Alcohol 99%+*** (available at electronics parts stores) to remove all traces of corrosion and water. If possible do not use "rubbing alcohol" as in some cases this is only 70% IPA or less, can contain additives and is not as effective. If you do have to use it check the label to verify the amount of IPA. The higher the percentage of IPA the better
Here is a links that describes what happens [[Electronics Water Damage]]
As always with electronics, especially surface mounted pcb be gentle when handling and especially when brushing away the corrosion. You do not want to remove any components from the board. Remove the shields that may be covering some components as the water may have got in under there. The ends of any flex cables and their connectors need to be cleaned as well
Hopefully after you have done all this the laptop ''might'' possibly work correctly again.
Here is the [https://download.lenovo.com/pccbbs/mobiles_pdf/l13_gen4_l13_yoga_gen4_hmm_en.pdf|hardware maintenance manual] that will help. Go to p.82 to view the procedure to remove the systemboard so that you can check what needs to be done.
If a component is faulty and needs to be replaced, here's the [https://pcsupport.lenovo.com/us/en/products/laptops-and-netbooks/thinkpad-l-series-laptops/thinkpad-l13-yoga-gen-4-type-21fj-21fk/21fj/parts/display/compatible?linkTrack=Caps%3ABody_SearchProduct&searchType=4&keyWordSearch=L13%20Yoga%20Gen%204%20%28Type%2021FJ,%2021FK%29%20Laptop%20%28ThinkPad%29%20-%20Type%2021FJ|parts list]. Click on ''Select Commodity'' and then scroll down to select the wanted part to find the ''part number'' for the part. Search online for the ''part number'', to find suppliers that suit you best.
If this process seems too daunting, take your laptop to a reputable, professional laptop repair service, experienced in liquid damage repair and ask for a quote for a repair. If you decide to do this, ''do it sooner than later''.