There's a massive number of people coming in, a big increase, and the Republicans have been blocking increases in funding for the US law enforcement agencies that deal with them (which, the left gives him grief for because increasing funding for ICE means he's a monster), and increases in the number of judges so there's not this huge backlog. So yes, there's a huge number of people and not enough US resources to properly care for them.
I.e. migrants are being left in limbo in inhumane conditions for long lengths of time. However, Biden's attempted several times to solve that and been specifically prevented. It's hard for me to see that as something which he is deliberately doing on purpose.
I addressed the thing that you said, which was perfectly fair although I feel there's a reasonable reason for that situation which isn't Biden's fault. The thing the other person said to me wasn't that, though; it was specifically that Biden had made family separation worse, which is absurd.
I am curious to know if this is a joke or not, I assume it is