House has a circuit breaker box and fuse box how can I switch the wiring from the fuse box to the circuit breaker box.can I use the old fuse box for a junction box.or can I use a different junction box .

Use a new junction box, the old panel will have too many openings that cannot be closed to act as a junction box.

Why not just do it right and replace the existing fuse panel with a breaker panel?

What is your level of expertise in doing this kind of work?