A SIM is a profile in a phone. An OTP is a short text. NonVoIPService separates those jobs: you order a number from the live catalog and read the SMS in the dashboard or through the API. Nothing is shipped and nothing is installed on a handset.
The steps are the same as a manual order. Add wallet credit, open pricing, choose a country and service that are in stock, and place the order. Copy that number into the site that asked for a code. When the text arrives, it shows on the order. The OTP without a SIM guide walks through the same limits.
This is not an eSIM. An eSIM is installed on a compatible phone and behaves like a carrier line you carry. The comparison is on the eSIM versus SMS number page. A VoIP softphone is a third product, and many apps reject those ranges.
Search-tool volumes for this phrase are estimates. They do not tell you whether a given app is in stock today. A short-term order with no SMS times out at about 20 minutes plus a 3-minute grace and returns the wallet charge. Use the number only for an account you are allowed to access.