Read the next few lines after the verse from John that OP posted.

I and the Father are one.” Again his Jewish opponents picked up stones to stone him, but Jesus said to them, “I have shown you many good works from the Father. For which of these do you stone me?” “We are not stoning you for any good work,” they replied, “but for blasphemy, because you, a mere man, claim to be God.” - John 10:30-33

Those listening to Him speak at the time understood His meaning. He was absolutely saying that He is God.

How else would you make sense out of statements like these?

Jesus said to them, “Truly, truly, I say to you, before Abraham was, I am.” - John 8:58

And he said to them, “I saw Satan fall like lightning from heaven. - Luke 10:18