Search for an asset in Adobe Stock and enable the Isolated Only filter to help find solitary objects.
Using the Select Subject option in the Quick Selection Tool, create a selection and add a Layer Mask to the image layer.
Repeat this process for the other images that will appear in your pattern.
Add a new solid color fill layer that is clipped into the image layer, apply a custom color, then set the blend mode to Vivid Light.
Repeat this process to create additional color variations, then save each version as a transparent PNG file.
Place, rotate, scale, and position your images in Illustrator, then select them and click Embed from the Properties panel.
Use the Pattern Options panel to design your pattern, then click Done to add a new swatch to the Swatches panel.
Apply a Freeform Gradient to another rectangle and choose some light colors, then position the gradient behind the pattern.
Check out this curated collection from Adobe Stock with more images that you can use in your next project.