No you dont need to land at the same airport that you mentioned in your eVisa application
Yes return or onward journey is mandatory while travelling on eVisa. Check FAQs on the eVisa website
https://indianvisaonline.gov.in/evisa/tvoa.html
The foreigner should have return ticket or onward journey ticket, with sufficient money to spend during his/her stay in India.
Also keep this in mind...
For
e-Tourist Visa (01 year / 05 years), the validity would be 365 days / 05 years
from the date of grant of ETA with Multiple entries and Maximum stay in India during one Calendar Year should not exceed 180 days.
For
e-Tourist Visa (30 days), the validity would be 30 days from the date of your first arrival in India. Double entries will be granted within the e-Visa validity period stamped on your Passport. Your first arrival must be between the date of issue and expiry of ETA.