Please help thank you so muc What are some means of explaining how species
are involved and what is the evidence to show?

A lot of ways you could take this. I’d stick with the classic Galapagos finch example. In this example the birds on an isolated island all evolved independently to occupy different niches of the island to cope with their being to little food for all of the species to eat the same thing. Some of the finches evolved larger beaks over time for large bits of food and others smaller narrow beaks for smaller bits of food. This shows that species need to and will differentiate with time to occupy different niches ultimately leading to evolution as generations pass