Make sure the area around the hole is clean and dry before applying either type of patch.
Cast iron gutter repair paint.
The undercoat acts as a preparatory coating on the guttering surface increasing the stickiness and durability.
For your cast iron drain pipes i would recommend painting them with red oxide primer first as that will stop rust coming through then dark grey oil based undercoat then your finish black and there is plenty of painting for your wooden soffits me personally i would use a white opaque stain which from my experience protects the wood the longest.
Gutter repair tape is a thin layer of foil coated with a layer of bituminous adhesive often on both sides of the tape.
The primer is absolutely necessary otherwise the paint itself might deteriorate the gutter itself.
After cleaning your gutters and leaving them dry for an entire day you can start applying a coat of primer.
Remove all gubbins dirt flaking paint and rust from the cast iron.
These gutter lining paints are specialist coatings that ensure all surfaces are waterproofed and uv protected preventing leaks for up to 20 years product dependant.
Evo stik metal epoxy putty.