Can you take your device to be fixed without knowing what's wrong with it?

I have an iPad, maybe around a few years old. Thing is, it functions fine but sometimes is unresponsive or blacks out when you try to open it. There are a few more bugs I don't really recall, because there are a bunch. Now, my question is whether they can do some kind of check up to see if it's possible to spot all the software issues and stuff to fix? Kinda like how they do an annual health checkup for humans. This may be a dumb question, but I'm just really eager to find out. I don't really have the money for a new iPad, especially because I'm pretty sure it's one of the most pricey ones out there. Does anyone know the answer to this/have or had a similar problem?