This one is tricky because experience as a noun can be countable or uncountable, it depends on the situation.
Experience is often an uncountable noun. You use it when you’re talking about knowledge or skills that you gained from living your life (basically what you have learned by doing, seeing or feeling things). You are referencing the whole of all the things you have done.
A: Tell me about your work experience. Do you have any experience teaching children?
B: I have don’t have any experience with young kids, but I have a lot of experience with teenagers.
A: You’re hired!
Experience(s) can be a countable noun (but in my opinion experience as an uncountable noun is more common). You use it when you are talking about a specific situation or incident in which something affected you. Not the whole of your experience, but just one thing that happened.
My worst driving experience was that one time when I fell asleep at the wheel.
A: How many negative restaurant experiences have you had?
B: Too many to count!
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