DNS App that block a website only at specific times

From what I understand, I’m using AdGuard DNS and NextDNS, both of which offer basic services for free. I tried subscribing to ControlD and CleanBrowsing, but they’re paid services only. For now, I’ve looked into AdGuard’s service a bit; I’ll try to do the same with NextDNS. Can you recommend other DNS services that can achieve my goal? What’s this discussion about Termux? What could be done with it?