I used to live in an apartment with two cats, they’ve never been outdoors, do you think is wise to let them out now that I live in a standalone house with a garden ?
It should be fine. With my cats, we kept them in the new home for a few weeks so they could get used to the new surroundings and watch through the windows, and let them out a little later. All went fine!
However, some cats might not want to go out after being inside for their whole lives, and they should obviously not be forced out.
You could start by going outside with them together
It is not a good idea to let your cats outdoors. Cats face a multitude of threats outdoors: FelV, FIV, other species, worms, ticks, fleas.
Our shelter does not adopt out to people who say they are going to let the cat outdoors unless the cat is a "barn buddy."