How can I test website simulating real scenario

We are building a website to replace existing one. I have got access to google Analytics data of the current site and I have found that in the last 5 years the hourly session peak number was 7650 with a avg session duration of 5 minutes, so, i can calculate the concurrent users, getting 638 concurrent users.

So, my first question is: how should I simulate that scenario? Should I launch all 638 users in the same second and keep them connected for an hour changing of page in the site every 5 minutes (average session duration) ?

In the other hand, what about find Throughput and latency of web site? for Throughput should I do a stress test and find number of users per second? how can i gent latency?

Thank you in advance.