Everyone is suggesting Immich, which is the answer if you want to self-host. But you say you are not very tech savvy, so you might want a service you don't need to self-host, and in that case take a look at Ente Photos.
You get end to end encrypted photos and don't need to do anything. They have guides on how to move your photos from Google Photos as well.
Ente can also be self-hosted, so you can compare what you like more.
Are there actually apps that refuse to work if you don't give them notification permission? I don't think I ran into one