Can you give me some tips?

I’ve come back to this game to give it another shot since it was originally released, I never really enjoyed it or got past the first entry into the future.

This time round I’ve just gained access to the prehistoric world, although I’m not sure I should visit here yet, and I have got parts of the Masamune sword, I beat the two kids recently, but I’m basically lost and without a quest log in game I don’t know what ime supposed to be doing next, any ideas?