Sitting alone in a rehab center is a military veteran. It is not pertinent to know his/her political perspective. Age, gender, color, ethnicity, religion have little bearing on how or why he/she needs you.
What kind of education or skill is required of you? A warm hand and humane voice will do.
Visiting a veteran is a marvelous opportunity for you and the vet to learn what friendship is all about. You may find you can learn to be a good conversation starter. Or you may learn to be quiet and listen.
You are human, the veteran is human. Bond as you will, you may truly help each other.
Find a veterans organization or program. Volunteer. Present yourself. America needs you.