These cameras exist in a lot of variants but there are some general similarities. Have you read a manual? There is one at IanBFoto:
https://ianbfoto.com/downloads/Mamiya 6+7/Mamiya 6 (1955).pdf
This many not be your exact camera, but it should get you close.
You have two issues, one is the poor focus, which could be incorrect film loading or rangefinder out of adjustment. The other is frame spacing, which from your description I think is that you aren't starting the film and counter correctly.
For the film loading, you have to understand how to route the film under the removable plate. To check the rangefinder, you should probably do something like improvise a focusing screen and magnifier (for ex a piece of translucent plastic laid across the film rails) and use it with the back open, so you can see if distant objects are in focus when the focus is set to infinity.
For frame counting, the manual above describes it. Basically you need to wind the knob and counter wheel to the position where the knob stops at or just before 1, load film, close back, wind it until you see 1 in red window, take picture. Then flip the little wind release lever, wind until it says 2 on the knob (you can check this in the red window), take 2nd picture, flip lever, wind to 3, and so on. This is pretty typical for a camera that has automatic frame counting but not wind/shutter interlock. That's why you need the little release lever.