Plant a mix of trees, shrubs and perennials. Different plants provide different foods and environments.
Do not use a load of pesticides on your lawn. I look at my neighbor's yard with the spray harmful chemicals lawn services and no birds.
We have at least 20 species of birds in our backyard.
You can grow certain types of flowers that attract butterflies. Look up "butterfly garden" for ideas. You can also put up bird feeders to attract seed eating birds and hummingbirds. And, the seed feeders will probably attract squirrels, too.