They should expect either to give you induction or to give you time to chat with people in your area of work who can give you the heads-up. "Should" is one thing, but seems like they are not that well organised.

I shouldn't worry about the clients not taking up your services. It's really up to your manager to give you the clients you are suited to work with.

Can you tell yourself to just hang out with the team for a few days, and look for some colleagues who are either experienced or friendly who you can chat to at the beginning of each working day.

I think this is your anxiety, not that you are incompetent for the work. You sound cool!