https://www.amazon.com/Dell-Inspiron-13-7348-Touchscreen/dp/B00WYF9LBS gives me a date of May 2015 so given the 300 cycle rating of the battery is indeed possible to wear out the battery in one year but this can be over 2 years old.

I'd take a chance on the charger first since it's about 20 bucks.
https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Delectronics&field-keywords=Dell+Inspiron+13+7348+charger

Then replace the battery since it's old enough to fail.
https://www.amazon.com/Noubi-tech-GK5KY-Battery-Inspiron/dp/B01M1Y8OXH/ runs 30 bucks.

If you can't bear to take a chance on either, take it to Dell or a shop for estimates.