Is it possible to still have a child even if you have endometriosis?

Absolutely. Though endometriosis can cause infertility, it is often very treatable. The most evidence-based treatment consists of excisional therapy using laparoscopy. This is where a skilled surgeon removes - using tiny instruments - the abnormal tissue. This is superior to ablation where the implants are burned. With excision, one can make sure all lesions are removed and confirm the diagnosis by pathology.
Absolutely. In general, endometriosis does not absolutley preclude conception, but it certainly can make it more difficult to conceive. Many women with endometriosis conceive quite readily.