You know it is illegal to use other people’s photos without their consent. You don’t know you might get into jail for copyright violation.
Thankfully there are websites which are providing free photos for commercial use.
Here is the list of those websites.
Pixabay is providing more than 1.5 million images for free and commercial use. You don’t even have to give attributions, however, attribution is appreciated. Pixabay has also their android app which is very easy to use.
Flickr is a huge photo website owned by Yahoo, here you can find images with different types of license.
You have to visit the website and search for anything you want then you will find the drop-down license list, you have to select commercial use allowed option. You will find a lot of free images for commercial use in this category.
Pexels is similar to Pixabay, you can use its photos however you want, no attribution required. Pexels have also their android app.
4.) Google images
When you search for anything under photos category, there will be a tools tab. In it, there will be a drop-down menu where you can select photos of different types of license like labelled for reuse.
Unsplash says they provide beautiful images and they are royalty free.
These are the websites which I personally use, there may be other websites which are providing free images.
You can also ask permission for the photos you like and if you want to use the photo, you have to ask the photographer and if he is OK with reusing it, then it is also an option.