The Brazil international had an underwhelming first full campaign at Camp Nou, contributing five LaLiga goals and two assists.
Coutinho acknowledged earlier this week he needs to improve to justify his hefty price tag, with Barcelona paying a fee that could rise to £142million to sign him from Liverpool in January 2018.
Manchester United and Paris Saint-Germain are rumoured to be interested in the 27 year-old, but he is keeping his attention on helping Brazil to Copa America glory on home soil.
"I do not know. The future, nobody knows," Coutinho said. "I am focused to play with the national team now."
Coutinho scored twice in Brazil's 3-0 win over Bolivia in its opening Copa America match, but he could not inspire his side in the 0-0 draw with Venezuela.