You can translate text, handwriting, photos, and speech in over 200 languages with the Google Translate app. You can also use Translate on the web.
Step 1: Download the Google Translate app
To get started, download the Google Translate app for Android.
Note: To translate images with your camera in all supported languages, your device must have an auto-focus camera and a dual-core CPU with ARMv7. For technical details, check your manufacturer’s instructions.
Step 2: Set up Google Translate
Tip: In version 6.10 and up, you can use a Dark theme in the Translate app.
The first time you open Google Translate, you’ll be asked to choose your primary language and the language you translate most often. To pick from available languages, tap the Down arrow 
To download both languages for offline use, leave "Translate offline" checked. If either language isn’t available for download, it will say "Not available offline."
Note: To download a language, by default, you must be connected to a Wi-Fi network.
Use Google Translate on the web
To use Google Translate on the web, go to Google Translate.