“We need someone with real hands-on experience.”

You need to hire a software programmer at your company. You don't want to hire a young programmer who's just out of school. You want to hire someone who's created similar software in the past. You're explaining what kind of employee you need:

We need someone with real hands-on experience.

(someone) with (something)

When you're describing a person, you can talk about the qualities and experiences they have using "___ with ___". For example:

I want to meet a guy with a good job and a good sense of humor.

Jason is a great carpenter with over 15 years of experience.

People with college degrees earn 30% more on average than people who have only graduated high school.

hands-on experience

When you have "hands-on experience", it means that you have done something directly, on your own. In American culture, having "hands-on experience" is usually respected and valued higher than understanding something in a more general way.

The adverb "real" is often included with the phrase "real hands-on experience". This just makes it sound even more hands-on.

You can use the phrase "hands-on experience" in all situations: casual, formal, written, spoken, etc.