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The slots you are trying to put these in expect number parameter, but you are placing logic blocks in it. You can put blocks that return numerical value there, these blocks return logical value (true or false).
I suggest you to check our tutorials collection playlist on our YouTube channel which contains many examples and tutorials that can help you get started with MCreator: https://www.youtube.com/playlist?list=PLAeL-oIFIEngE6jRgFYeFMfuj8WQsO3Ei