Questions about: cracks

This house is about 20 years old and we purchased it last April without seeing any of this stuff. The inspection came back OK but we found a decent sized foundation crack on the walkthrough under some insulation (good times.
I purchased and moved into my first home about 3 months ago. It's originally a home built in the 1930's. An investor bought it last year to completely gut and flip the property
Q. I have to make an unexpected repair to my poured concrete foundation. A water leak led me to remove drywall in my basement, and to my surprise, I discovered rows of holes 5/8-inch diameter in my concrete walls
It will either do so through small, existing cracks, or it will push through and create new cracks. The first thing to do is repair the area that is leading so much moisture into the wall. The problem is normally around flat areas like parapet walls