There is very little similarity between present day power plants which use nuclear fission, and any possible nuclear fusion plant of the future
Chemical synthesis form a new molecule; nuclear fusion form a new atom.
nuclear fusion
Nuclear fusion has been used for nuclear transformation, which is the production of new materials by fusion, and for the type of specific type of transformation called nuclear synthesis, which is the production of materials not normally found in nature. It has been used in nuclear bombs, specifically fusion bombs or hydrogen bombs. There is hope that nuclear fusion can be used to provide power for generation of electricity, though this has not yet been achieved in a practical system. There is a link below to an article on nuclear fusion.
Nuclear Fusion
No, not yet. Maybe in another 20 years when its perfected (which they have been saying every 20 years since they originally began work in the 1950s on lab prototypes of controlled nuclear fusion reactors for power generation).
The Sun gets its energy from nuclear fusion - converting hydrogen-1 into helium-4.
Nuclear fission is used in commercial power generation. We don't use fusion yet in that application because we have not conquered the technological problems in doing so.
Stars undergo nuclear fusion in their cores, and so generate energy; i.e., light and heat. No nuclear fusion, no energy generation, ergo not a star at all. Generating light and heat is how we can tell a very large planet from a star. If it isn't generating energy from nuclear fusion, then it isn't a star.
Combining two atomic nuclei is called nuclear fusion.
Fusion is a nuclear reaction.
They are not similar, as fusion and fission involve changes to the nucleus whereas chemical energy involves the bonds between atoms
The idea of nuclear fusion occurring at room temperature is called cold fusion.