Patterns are nothing but decorative design found firstly in nature. Some evident examples include the white clouds on blue sky for a random pattern. The leaves of a fern form a regular pattern....so on and so forth. One can start identifying millions of examples in nature.
In the world of interior design, patterns are nothing but some form of artistic or decorative design found on wall, fabrics, paper, accessories etc., Something that is not plain is considered to be a pattern. It can be regular or random. A regular pattern is something that would follow a sequence or a logical order whereas random patterns do not follow that and would just be irregular. Some common patterns include polka dots, zig-zags, checks and stripes etc., Patterns can also reflect a particular period of style.
Textures are sturctures of interwoven fibers or elements. One can clearly identify the physical composition of a texture. Textures can be smooth, grainy, or rough. While most textures are physical in nature some can be visual too... like the painted wall would be considered more of a visual texture than physical. Some of the examples can be seen here....
Regular pattern with Woven Physical Texture
CREATING TEXTURE WITH A WEAVE