You are probably going to have this problem often with glasses from Firmoo...I am on my second pair from Firmoo. The first pair broke after 2 months and my second pair have already broken as well. Very poorly made.
Superglue can help fix your problems. But there are other steps to you must to do. You need to prepare some tools and articles before doing it. You must glue the inside part of broken eyeglasses as well as the outside of these two parts. So it is a little complicated. You'd better have a look at https://www.instructables.com/id/Repair-plastic-eyeglass-frame-with-thread-and-supe/. The guy in the article will teach you how to fix your broken glasses.
You can use construction adhesive such as liquid nails to glue your broken eyeglasses. You can glue a plate across the break on the inside first and then take a piece of metal or even plastic to glue it across the break. I think this is a little difficult for me to handle. But if you are good at hand work, you can have a try. Hope this helped!
The glasses from Firmoo are very cheap. And the after sales services are very good. If your glasses are bought from Firmoo, I strongly suggest you to contact with the after sales services and tell them what's wrong with your glasses. If you get a pair of broken glasses from them, they will send you another pair of new glasses. Of course they will not charge you again. If your glasses broke after you have worn them for a few days or a few weeks, you can also connect with the after sales services. They may send you a pair of new glasses for free or make you compensation according to which kind of material your glasses are.
Plastic eyeglasses are easy to get broken. So you must be careful in wearing them. If you don't drop them on the floor by accident or don't sit on them (I just did this last night. I put my eyeglasses on my bed when I was trying my new cloths. I sit on them by accident. God, I just totally forgot about them. So they broke into two parts), they won't break that easily. I don't want to repair them anymore because they are so cheap. I want to buy a pair of new plastic glasses.
Firstly, you need to tell me that where your eyeglasses are broken.If it is caused by losing screws, you can tighten the eyeglasses frames with screws. However, if it caused by broken of the plastic frame such as arm or nose bridges, it is very difficult to fix them. Maybe you can fix them with adhesive tape by warp the broken part. It looks ugly if you do that. If so, you'd better buy a new pair. And you can expected to get some cheap but good quality eyeglasses from online shop.