Suggest Treatment For Itchy Pinkish Rash On Torso

I have an upbody pinkish rash. It itches no alot.
No fever it.. My fear is I had chicken pox when I was younger and have not had the shot for
it. Also, I had measles when I was younger.

How can I distinct the rash. It is on my back and on my stomach. Just patches, not thick ones.
Thanks