Subscribe (verb)

1. To sign up to receive or access something on a regular basis, such as a publication or service.
2. To make a commitment to support or contribute to something, such as a cause or organization.
3. To agree to a proposal or statement, such as in a legal or political context.

Origin:

From latin subscribere, 'to write underneath'.

Examples:

1. She subscribed to the monthly magazine for her son.
2. He subscribed to the streaming service to watch movies and TV shows.
3. She subscribed to the cause and made a monthly donation.
4. He subscribed to the treaty and promised to follow its provisions.
5. They subscribed to the proposal and promised to work together to implement it.