K8055 higher output

I would like to make analog output higher then 5v like 10v, is it possible to somehow wire both outputs in series?

Sorry - that is not possible. Both of the analog outputs have common ground and can’t be connected in series.

If you are using a higher voltage to power something else then you can power an op amp with the higher voltage and with a couple of resistors give it a gain of 2 to get what you want. If you search on the internet you will find circuits to do that.