1-in my modding process,i only use .vkp instead of codes.(vkp is a patch file)

2-turn off phone,reinsert battery,then press and hold 'C' on the phone button then connect to usb cable.windows will say 'New hardware found-->Flash hardware found blablabla'. You have to install the Usb flash driver(DOWNLOAD) when the Found New Hardware windows pop out.

3-you have to use (XS++) to make GDFS backup,and to reflash ur firmware(also known as Main) therefore, XS++ is a software to recover your phone if patching failed.

4-make a GDFS backup using that (XS++) and place the backup(.bin format) at a safe place in your pc for safety.

5-you have to use Jdflasher to patch the .vkp into phone. Jdflasher is a FAR Manager plugin. Therefore,you have to set up them like THIS

6-Follow these steps:
01) Download a copy of your Firmware(recommend latest firmware) into your pc. It is in .mbn format.(search them through google if you don't know where to download) Latest Firmware for K810 CID52 Red is HERE.
02) Place that Firmware(.mbn format) in Far\Plugins\jdflaser\2020_52
03) Drag the main into qamake.exe
04) Let it finish. It shouldn't take more than a few seconds. A new .vkp file will appear there after this step is done.
05) Open Far Manager, press Alt-F1 and select "just da flasher"
06) Select as phone "db2020", maximum speed and click "jump down into a large rabbit hole"
07) As soon as it connected select "bflash"
08) You will need to reinsert the battery 3 times (it will tell you when to do that). Don't leave your computer.
09) As soon as it finishes, it will tell you to reflash your Main. We're going to do that now.
10) In the right pane navigate to Far\Plugins\jdflasher\2020_52
11) Select your main (make sure you select the .mbn file and not the .vkp file!) and click copy. In the 1st dialog don't change anything, just click copy. In the 2nd dialog make sure "flash babe image" (the 1st option) is selected and click flash.
12) After flashing is done, select the VKP patch that is in Far\Plugins\jdflasher\2020_52 and press copy. Don't change anything on the 1st dialog again. On the 2nd dialog make sure that "Process vkp patch" is selected and click "flash". It should take a few seconds.
13) Now you can apply any patch you want!
14) After you finish, make sure you click the 3 dots ("...") and select "yes"

Next time you want to patch your phone, you won't have to do the same things again! Before connecting your phone, select "qa2020" instead of "db2020" as your phone model. Then click bflash and jump to step 13