ERROR: client and server don't have same version (client : 1.21, server: 1.18)

[Apelsin2020]

Hello, first time working with docker, so don't swear too much. I follow the instructions, but I get this error:

docker.errors.InvalidVersion: API versions below 1.21 are no longer supported by this library.

In order not to receive it, I install the old version like this

ERROR: client and server don't have same version (client : 1.21, server: 1.18)

And then I already get this error and do not know at all how to fix it

thank you in advance