You can buy one-off or recurring data plans from eSIM mobile service providers such as Ubigi.
A one-off data plan is a data plan that you buy for a one-time use. A recurring data plan is a mobile plan with a data allowance that is automatically renewed on a monthly basis. Ubigi proposes 6 or 12 months validity-period recurring data plans.
You will also pay upfront if you buy a recurring data plan, like a one-off data plan. You will not be billed monthly but at the date of the initial purchase for the total duration.
Ubigi provides recurring data plans for 6 or 12 months, depending on data plans.