New Job

I have an interview for a new job on the 23rd of this month. I’ll be 8+5. The job won’t start until after I graduate in August. I’ll be around 20-21 weeks. Should I say anything? I’m leaning towards waiting for an offer but telling before I accept. I will be working in a hospital lab. I don’t want them to think I’m being shady but also don’t want to get turned down (I know it’s illegal but it’s hard to prove). Any advice?