When thinking about what service to offer on Fiverr, it can be a good idea to look at the gigs posted by other sellers. What do they offer? How much do they offer for $5 (if anything), and what costs extra? What's their delivery time? How did they describe their offer, and what would you change in the description if you were to offer something similar?
Gigs posted by other sellers can be a source of inspiration, and it's easy to think to yourself: "Hey, I could do this, too!" Pretty soon, you will run into another service you could offer, and another, and yet another one.
It's great, but... Do you really want to offer that particular service? Do you want to do something like that time after time after time? Or in bulk? How long do you think it will take before you feel sick of it, before it's too much, before you run out of ideas?
"I can do that" easily turns into a trap. The fact that you can do something doesn't mean that you actually want to do it, especially not over and over again, just slightly different. It could easily lead into a burnout, make you feel exhausted, maybe even lead you to believe that Fiverr isn't for you.
Well, maybe Fiverr really isn't for you, and maybe you've just chosen the wrong service to offer. Maybe you've chosen something that you can do but don't find it fun and don't truly enjoy. That's all right; it's perfectly fine to try out things, to try offering something, and then decide that you don't actually want to do it.
Keep looking. Keep trying. Keep coming up with new services, until you find those that you really want to offer, and won't get bored of for a long time to come.
Keep trying, find out what it is that you want to do, and you will succeed.
