I bought a bunch of cheap’ones from Amazon, Hisee I think is the name. You can use them with SD memory cards or, if you are wealthy, have them upload to the cloud. I think I paid $15 each. I can view them with my phone but you have to be on the cloud subscription if you want to view remotely. I think all camera companies require a subscription to view remotely.
Thank you
Many, dare I say *most*, cameras that connect wirelessly via internet, try very hard to sell you cloud service with advanced AI features that are not available with their local microSD-based card storage, but it's not universally required.
Services vary - some will save 10-second clips to the cloud without a subscription, EVEN IF YOU DON'T WANT THEM TO.