Well, i'm not sure I understand you completely...
The Help files are really helpful!
You have a number of pre-defined Pen Sets in the program. There's a list at Options>Element Attributes > Pens & Colors.
If one of them suits you, fine, otherwise customise and save one of your own. You can use any color and pen width for any pen. I usually use an Autocad standard pen set of my own because it makes conversions easier.
Now open your layout, select the view in question and right-click. Select Drawing Selection Settings. In the dialog, open the Properties tab. There in the lower left, select the pre-defined pen set you want. Then, on the right, you can override it with greyscale or everything black if you like. Click OK.
If the DWG refuses to display the way you want it after the above excersise, you can workarund it by importing the DWG into a separate .pln document and then Hot-link that into your current project. This will give youeven more control.
If none of this works, I don't know.
AC4.1-AC26SWE; MacOS13.5.1; MP5,1+MBP16,1