"Reject applications"

Accept requests - the request acceptance mode for your resource can be set for a specific time (in minutes, up to 1440)

It is also possible to make a special effect of Telegram's system notification such as - "The bot wants to send you a message". To do this, you need to set the request acceptance time to more than the time for sending the second message.
More details about this effect here

Ignore applications - a mode for manually accepting requests to your resource. You moderate and accept the users you want yourself

You can also create a special effect for Telegram system notifications, such as - "The bot wants to send you a message". To do this, you need to set the application acceptance time to be longer than the time for sending the second message.
More about this effect here