Bot Telegram without webhook

I am using the telegram Telegram bot to create a bot. I can already send messages, files, etc. I am creating commands for the "/ setcommand" bot and I want this command to do something, a routine, run a php script, js, etc. I saw in the documentation the use of webhooks, I believe that roughly, when executing a command with bot the consumer will be the telegram that turns in my infra via HTTP consume of a rest, am I correct? The doubt is as follows, how to make the bot execute commands without I need to provide a url / webhook for it, eg: I give POST HTTP in several contents, I believe it stays in cash on their servers, as I do a bot command consume something which has already been sent via the API to the telegram?