#2 As has been noted, the biggest problem with the border is Biden's border policy(s). Congress "could" tackle part of that, but even if Congress was united on the general policy direction, it would take them literally years to hammer out the specific details in the legislation. That's what an Administration has hordes of people employed to work on: All the specific rules, regs, and so on. That legislation is even tougher to knock out when the legislators know the Administration will try to subvert it.
Possibly the best bet would be to pass legislation addressing a couple specific Biden policies, which legislation Biden is sure to veto (and likely dies in the Senate anyway), and use that in the fall campaign.
#3, there's a critical election to win, and to be honest, the Pubbies and Trump need the border issue as a strong second behind the economy, to do well. I kinda hate to say it, but "never let a crisis go to waste." In this case, the last thing we want is some squishy compromise bill to somehow get through, and then the Dems can crow about their wonderful bipartisan legislation to finally fix the border - "damn that Trump for ruining the border, but we've fixed it" - and other such BS.
OTOH, without aid soon, Israel and Ukraine are going to be in big trouble. The Ukraine situation is obvious - they need ammo and they need more than popgun weapons, even if they have made great use of what they've received so far. Israel's economy is getting hammered - a detail isolationists conveniently forget. Plus, If Iran thinks Israel is vulnerable, they will tell Hezbollah to attack in earnest. 120k rockets? 150k rockets? Most likely, we would HAVE to intervene unless we want to see a battered Israel resort to firing off, say, 1/4 of its nukes, and God knows where that would lead. China... Needs an immediate reminder we can help our Asian allies make Chinese aggression very, VERY costly. In none of those overseas areas can we wait around, because if our enemies make a move, it will be before Biden (hopefully) gets the boot.
For one thing, you are asking a dishonest question. The issue of Israel and Ukraine is not some problem they have with illegal immigration from an otherwise friendly (mostly) country.
Israel has been a friend (well except for the USS Liberty business) since its creation. It is the only democracy in its part of the world. Ukraine, not so much. I do appreciate that Russia needs to be stopped in its expansion but there are a lot of our allies in the region who should find Russian expansion in Europe more threatening than us.
And then there’s who’s going to distribute all of this money. The guy whose ineptitude brought us to this mess in the first place. Russia/Putin, Iran/Hamas/Hezbollah weren’t quite so adventurist back when Trump was President.