1974 Dart

Welcome to the site!

The best advice I can give you is to take your time with the car and don't rush. First and foremost, make sure the car is safe. Start with the brakes. Don't worry about an oil leak until you are sure the car is SAFE.
You can check the oil and add when low. Are the tires good? I don't just mean tread, but are they old, do they have any small cracks?
Also, get the car running well as it is now, only then start changing things like adding a 4 bbl.
Get a factory service manual and parts book. Join a local car club.
Keep notes of what you need and want. Most of all, HAVE FUN!