I'm not Pakistanis
But yeah what you mentioned can be thought about by Pakistanis military before launching the war.
For one Pakistan can trade Kashmir with India for peace to reign between both sides and avoid India attacking Pakistans Eastern flank when Pakistan is at war with Israel. So Pakistan will need to first sign a peace treaty with India or better still recognised each other Kashmir held territory as defacto border between both countries..Just so Pakistan can focus on the war with Israel peacefully without being worried about India..
It's true that the US/West will sanction Pakistan and cut all military supplies.. However, Pakistan can count on her neutral all weather friend China ..Hopefully China will supply Pakistan with military ammunition, supplies to keep Pakistan in the war. Else Pakistan won't be able to fight for long(not even for a couple of months to be honest). So Pakistan will need to sort a deal with China to guarantee China will support them financially and militarily, just so Pakistan doesn't get even more bankrupt than it is already, else they cant fight Israel for long. So those things need to be sorted out first before an invasion.
Pakistan will also need to invest more in her army, airforce and navy to make the invasion more successful, this will mean Pakistan will need to sort a deal with neighboring countries in the middle east from where her troops and equipment can be station and used during the war. Syria, Lebanon, Iran(maybe even Iraq)are good choices. They will need to provide their territory for such an operation ..I believe they won't have much issue with doing so.
For your last point , none of them will use nukes, it will be a conventional war. Just like in Ukraine , Russia won't use nukes, everybody knows that. And even less likely so since Pakistan and Israel are nuclear powers.
So it's doable for Pakistan. Pakistan just needs to be willing to sacrifice their country for the great Islamic cause. Afterall they are the only country in the world who was created for Islam alone. So they need to be able to sacrifice themselves for the greater Islamic cause. If not what was the point of establishing the country? So I understand
@AA_ point.