LineageOS has no actively maintained builds for Huawei devices (but they used to, fairly recently) and it’s a very limited selection of older devices for /e/OS.

idk much about rooting but if you can do it on the stock OS, you can install microG and get bare minimum features like push notifs working.

also FUCK google for locking essential features behind their pooprietary services. they will not be spared in the revolution.