If any of these problems are the result of a weather event, contact your insurer to see what kind of coverage you may have. Taking a series of photographs now to document the damage you're dealing with could be very helpful down the road. After that, first deal with the roof. Temporary placement of tarps to keep the interior dry is a good idea until permanent repairs can be made. Contact your city or state authorities for advice on where to get help dealing with the mold and the foundation. An experienced local contractor should be able to give you a clearer idea of what needs to be done and what the priorities should be.

Did you just buy this house or have you been living in it and it's slowly been degrading around you and you just finally realized that it's a mess?

How utterly depressing and overwhelming! I'm so sorry your house is in such disarray.

I recommend starting with the mold. That can affect your health.

"I recommend starting with the mold"

Fix the roof and water intrusions first or you are just peeing into the wind and the mold will be right back..................

That would be starting with the mold. Dot, dot, dot.