Of course you go in. How else would her father farher you?
The farher usually lasts about two or three hours, but sometimes more, if the potential future shver is not getting a clear enough picture.
During the farher, you should answer confidently, but not so confidently as to challenge the potential future shver’s self perceived superiority. This can be tricky. The standard blowing the dust off of the potential future shver’s gemara is not actually recommended, except in extreme cases.
On the date, act obnoxious. You don’t want the girl marrying you thinking you’re a nice guy. Then you’ll have to live up to it. So act like a jerk, and then when you’re married, be your mediocre self, and she’ll be pleasantly surprised.
Also, when she comes home, if she tells her father (that’s your potential future shver) that she wants to marry you because you’re such a nice guy, he’ll think her priorities are all messed up because she’s not focusing on what’s important, that you’re such a big lamdan, and he’ll call it off.
Your friends and rebbeim might tell you differently, but trust me on this. I’ve been dating for over thirty years now, so I have more experience than all of them put together, and I know what I’m talking about.