>>7655451Baumann spends 6 whole pages telling you why cameras are insufficient and providing examples of how photographs from the same spot but with different settings look radically different.
The tl;dr is that a camera has a shittier range of colors and values compared to the human eye, has immobile and non-eye-like focal points once a photo is taken, alters how detail is shown and has a completely different field of view. Among other things. A camera lens is just not what an eyeball is, much less a pair of eyeballs.
You don't have to go outside though. Make art from things inside. Or sit at your window. There's something weird that happens when you are translating 3D objects into 2D that greatly assists with painting from imagination too - I think it's the fact that you have to consciously decide on a lot of the elements, as opposed to a photo doing it for you.
This isn't to say you should never do it, especially for intentional images, but as practice it's pretty necessary. Like get some anime figurines or tank models or something, a strong lamp, thendraw/paint those. Borrow your grandma's precious moments figurines or ceramic christmas diorama or nativity things. Go to a model train shop and ask if you can sit and draw the displays. Go to an antique store or jewelry shop or so on and draw the things there. There are all kinds of options to have air conditioning while drawing shit you don't own, and store owners are often pretty accommodating because it means their store isn't empty.
You don't have to paint fruit or trees.