Learn English – Is the lamp ON or IN the ceiling

If you’re going to use “driven” in this context, I think you’ll need to go with “by” as your proposition, followed by the person or (more often) the concern defining the conversation or moving it forward (not, as in your example, the destination of the driving).

Example: The conversation was driven by Andrew's love of all things British.
or: The conversation was driven by their shared desire not to harm the bees.

To stay closer to the statement you’re looking for, you rightly suspect that “steering” will work perfectly.

As for the preposition, I recommend “toward(s)” as in:

I managed to steer the conversation towards school bus fires so that I could tell my heroic tale.

In such cases, as a learner, I suggest that you check the Oxford dictionary. It always provides many nice examples through which you can discover the idiomatic sentences and collocations. By the way, the idiomatic preposition is to.

You can say

I plan to travel to China

In terms of your second question. You can use those prepositions in different context. For instance, you can say:

• It's really interesting to travel in groups.
• It's really easy to travel in the USA.

(Using "in" when talking about the place itself like USA, Canada,... and when describing the way of traveling)

Or

• I traveled for a month.
• I traveled for a business goal.

(Using "for" when talking about reason or duration)

By the way, our native friend on ELL can provide you with more accurate and idiomatic examples. I thought It's a good idea to mention some myself.