How could you get started in ‘Agile’ methodology?

Get an understanding of everyone’s skills and their way of working.

Develop your overall team goals. e.g. Always putting the customer first in decision making.
Understand the value of a multi-disciplinary team structure or Subject Matter Expert (SME) teams.

Work out whether Agile is the right delivery methodology for your business by researching it’s advantages.

Read SPRINT Marketing for shorter iterative solutions: https://www.thesprintbook.com/

Or read an excellent overview of GOV.UK Service Manual on Agile delivery