Contact us at https://t.me/thewchannelbot because that cannot be done by yourself
No. Currently the service is completely free. You could see ads on the website and sometimes an advert could be shown to your users that use the shortlinks
TelegrAd has a free version with limitations and another paid version with higher limits. Throughout TelegrAd the free channels are marked as #Basic and the channels that have a subscription to the platform are published as #Prime
Sorry, the payment is not enabled yet.
Add the bot https://t.me/telegradlinkbot or @telegradlinkbot to your channel and allow him to send messages and add users (to generate own invite link)
You have unlocked several timers depending your channel billing.