Do I need to request the website code from the client?

I landed my first gig and he liked my proposals. I went today to start working on the project without getting the website code directly from the client.

I tried using a certain web crawling program and then hosting all the files on my hosting. It seems so far to work fine on my Desktop, but the mobile version is quite messed up (For example, no mobile-friendly navigation bar on my hosting that was originally there).

I was just wanting some advice on where to proceed from here. Would you all recommend I just contact the client tomorrow (he’s not super tech-savvy), or is there something else I can try to get this working? I definitely think next time it may be best to get the code upfront. Thanks for any help or suggestions for further research!