how we can use F5 BIG-IP with licenses LTM and GTM to manage Internet traffic on two connections using two different Internet service providers (ISPs)?
It sounds to me like you're looking for classic link load balancing. So.. do you want outbound link load balancing or inbound? Here's how it works with LTM / DNS:
Inbound: set up a WIP in DNS for each service. Each SP has a VIP. (btw, you can accomplish this with F5 XC Cloud managed DNS and LTM. don't even need DNS license for that.
Outbound: Set up aa all-ports forwarding VS on the inside leg of your LB. The pool for that VS has each router's GW as members. Set up persistence as you like it.. source / dest.
