Answer:
Yo tengo enfermo/a.
Step-by-step explanation:
"I" in Spanish is "yo".
"am" in Spanish is usually "estar". However, as this is a state of being, we use the verb "tener", which means "to have". However, we must conjugate "tener" in the yo form: tenga.
"sick" in Spanish is "enfermo/a" (o or a depending on if you are male or female, respectively)
Putting it all together, the sentence is:
Yo tengo enfermo/a.
Hope this helps!