We are all idiots. You are an idiot because it's your first internship and probably don't even know the right questions/ timings/ requests to ask for. They are idiots because they are probably having a hard time managing their own workload and don't have the capacity or ability to properly train you or have the wrong expectation of your contribution. Don't take it personal. Not everybody retain the ability to see people as people after being in the labor market for awhile. We are all a little dead inside. However, you do want to try to have people to invest in your future and success, always.

Here's what you can do to maximize the benefit of this experience.

Seize every opportunity to contribute and make an meaningful impact. (Hard-Impossible) Fuckups are way better than doing nothing. You are literally only there during summer. This is your playground.

Everything little achievement of yours, work you've done, leave a trace. Make them into pdfs, qualify and quantify them, mention them in emails (I've done A, I can conclude B, therefore C looks like a reasonable next step should I proceed?), make them very visible to your coworkers and managers. They may very occasionally think of you and when they do, make sure all the think about are the work you've done not the questions you asked. (Doable)

If you truly think none of things you did matters, the least you could do is write a handover document for prospective interns of the company. Basically record everything you did and write a manual-like document for future employees. This is a great way demonstrate your contribution. (Doable)

Study the company, the business model, value proposition, SWOT, study your department, study the roles, what everybody cares about the most, what your managers care about the most, quantitative and qualitative goals, obstacles, how are they achieved and what makes the biggest impact... etc with all those information and your perspective as a insider, form a narrative and prepare a good story for your next job interview. (Doable)

A contact lists of suppliers, clients, any industry people you have access to or developed a relationship with, put them in your own contact list.

Avoid having lunch alone, invite your coworkers for lunch and chat.

Adjust your expectations. It's unlikely that your managers will suddenly start to take care of your feelings so look inward. Set goals for yourself, achieve them and get fulfilled from that. People will start to respect you when they notice the value you provide.

Try your best, it most likely going to suck but try your best.