I need help with my problem. I had to uninstall docker desktop, so when I finished work SpringBoot application then removed Docker Desktop. I found that,I can use only docker cli so based on this tutorial/movie, I added changes with commands
https://www.youtube.com/watch?v=SE3EAT9SCP4
generall, the instruction consists in entering commands in the console one by one, below:

wsl -l -v
wsl --set-version Ubuntu 2
sudo apt-get update
sudo apt-get install -y apt-transport-https ca-certificates curl software-properties-common
libssl-dev libffi-dev git wget nano
sudo groupadd docker
sudo usermod -aG docker username
Id username
curl -fsSl https://download.docker.com/linux/ubu...  | sudo apt-key add
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu
$(lsb_release -cs) stable"
curl -s https://packages.cloud.google.com/apt... | sudo apt-key add
echo "deb https://apt.kubernetes.io/ kubernetes-xenial main" | sudo tee
/etc/apt/sources.list.d/kubernetes.list
sudo apt-get update
sudo apt-get upgrade -y
sudo apt-get autoremove -y
sudo apt-get install -y docker-ce containerd.io
sudo apt-get install -y kubectl
echo "sudo service docker start" &gt&gt ~/.profile
exit

but I had problem with docker-compose , so I found out that, I can use Rancher Desktop instead Docker Desktop so I installed Rancher. I set up some container with db and connect with Spring-boot application but after that I got error.I switch off Rancher and closed it and I tried run application without db and expected exception about problem connecting db but still the problem with kubbernetess (details below)
Caused by: java.io.IOException: Invalid DER: object is not integer at io.fabric8.kubernetes.client.internal.PKCS1Util$Asn1Object.getInteger(PKCS1Util.java:125) at io.fabric8.kubernetes.client.internal.PKCS1Util.next(PKCS1Util.java:55) at io.fabric8.kubernetes.client.internal.PKCS1Util.decodePKCS1(PKCS1Util.java:46) at io.fabric8.kubernetes.client.internal.CertUtils.createKeyStore(CertUtils.java:116) at io.fabric8.kubernetes.client.internal.CertUtils.createKeyStore(CertUtils.java:197) at io.fabric8.kubernetes.client.internal.SSLUtils.keyManagers(SSLUtils.java:128) at io.fabric8.kubernetes.client.internal.SSLUtils.keyManagers(SSLUtils.java:122) at io.fabric8.kubernetes.client.utils.HttpClientUtils.createHttpClient(HttpClientUtils.java:78)
I didn't change except this, so now I cannot run Spring application . They use kubernetess-client 4.1 After that, I did:

1. I removed completely ubuntu from my Windows 10
2. I removed all application which were in wsl, docker desktop and rancher dektop. I installed everything again, I mean
3. I installed ubuntu-20.04
4. I installed docker and docker desktop such like before
   but I still cannot run Spring application the same error
   I don't have no idea what happens. Wheter changes from movie changed something config or when I used Rancher Desktop with kubernetess something changes I thought, all changes from tutorial I added in local ubuntu but now I'm not sure I would be very grateful for the answer because I have been working on it for the second day and I have no idea