You can't "just deport them'.
Legally you can't deport if they are likely to receive inhumane or degrading treatment that fails below a level incompatible with human rights, as set out in the ECHR, in their country of destination.
If we leave the ECHR it affects our ability to trade with our European neighbours and it will put even more additional barriers up with them over border control.
The EU will not stand for a cutting of human rights without making life miserable for the UK. Even if it harms their financial interests because human rights are so central to the entire workings of the EU which was born in the post WW2 era of recovery and healing from the scars of the war.
Not to mention leaving the ECHR would have a massive impact on all of us in terms of standards of living and our own rights. It would allow big businesses and the state to exploit workers to a much greater degree, just at a time when there are so many questions about AI and billionaires and surveillance states and population control in ways which mean we almost become slaves to those in power with zero accountability. Which is really what Farage is after for his own financial gain. Under those circumstances poverty and crime are not likely to decrease. We are more likely to have even more inequality and even more acts of desperation. There's only so many people you can deport before you start to have such a problem that you have to start finding another type of Solution.
If you don't understand this, then you are going to be sorely disappointed.