There is no concept natively of archive for intersection of specific custom post type with specific taxonomy.
There are multiple approaches here, but all will take some tinkering:
- you can adjust category term archives to include your CPT (via
pre_get_postshook) - you can extend custom post type archives with endpoint to filter them by category
- probably more ways, it gets pretty arbitrary outside of native functionality
In your specific case I find it a little strange that CPT in question is a “Blog”, since that’s what native posts already are (and likely easier to go with for, well, blog).