Is there any possibility to have access to logs via internet?
No. If you really want to access you hub and the logs from the internet, I would recommend looking into setting up a VPN connection at your home. Some internet routers can do that for you or you can use something like a rPI to host a VPN server.
Thanks , I have one more question.
I have enabled reporting of valve state in my eurotronic spirit z wave thermostat. I'm receiving current valve state in logs for each thermostat . Can I transfer this values somehow to my dashboard?
Do you see the valve state listed in the "Current States" list when you look at the device in Hubitat?
If so, you can add a tile to a dashboard and use the "Attribute" template to show that state.
Unfortunately not, I can see it only in logs
Than there is no way to get it on the dashboard unless you code your own driver for the thermostat. Needless to say, that is only an adventure for a real expert in zwave driver programming as thermostats can be one of the most difficult devices to code for.......