There are countless websites (e.g., UnlockBase, DoctorSIM, UnlockRiver) that calculate unlock codes using your IMEI.
Remember that patience is critical. If one method fails, move to the next. The TR118 is a resilient MediaTek device, and even if you get a "dead boot" error, you can usually recover it by flashing the official stock firmware using SP Flash Tool. tecno tr118 unlock