Mistakes can "brick" your phone. Proceed only if you are comfortable with technical troubleshooting. 1. Preparation and Tools You will need a Windows PC and a reliable USB cable. Is safe to install custom ROM? - OnePlus Community
Because of its MediaTek chipset, developing full "from-scratch" custom ROMs is challenging. Instead, the community relies heavily on Generic System Images (GSIs) and a few specialized ports. GSIs (Generic System Images): Most users install GSIs like LineageOS (patched) samsung a01 core custom rom portable
Users have reported success with /e/OS (privacy-focused), Resurrection Remix , and ZenX OS . Essential Files & Tools Mistakes can "brick" your phone