Bonjour,
ex 1 :
a. If I had a garden I could/would grow vegetables.
b. If I was a superhero I could/would save the world.
c. If I was in London I could/would visit big ben.
d. If I was a castaway I couldn't/ wouldn't hunt.
ex 2 :
je sais pas vraiment...
j'espère que j'ai quand même aidé.