I’m afraid UCs are going to be off the table and universities that don’t offer merit are going to be difficult to fund for your first child.
Your US citizen child will be eligible for Pell grants if you don’t make much money and no matter how much you make that child will be eligible for 5.5k in federal loans per year (a bit more each year through senior year); in additional they’ll be considered a resident for in state public universities’ tuition and will be eligible for institutional grants (and, in PA, possibly PHEAA ).
So their situation will be MUCH easier.
As a result, you’ll have to focus some of your savings onto your first child, and explain why to both children so the second one doesn’t feel “disadvantaged”.
Has your junior child taken the SAT or ACT?
High scores+high GPA can often yield good merit aid.
You can focus on universities that meet need for internationals they admit, although they’re need aware; your son coming from a US state will be in his favor (he’ll compete with students from his HS, not with students from all of India) and I assume you have a US-levek salary which should be higher than most internationals who need FA.
That being said, things will be much easier if your child scores really high on the SAT or ACT.
Run the NPC on Lafayette, Franklin&Marshall, Bucknell, Dickinson, Lehigh, Susquehanna, St Joe’s, perhaps depending on how strong his academic record&ECs are Haverford and Penn. If the NPC looks like costs would be possible without a loan, visit, reach out. (Keep in mind the NPC is designed for US citizens so remove the federal loans and consider the amount the lowest you’d have to pay.)
Add PSU, Pitt, Temple.
AFAIK PA contract/state related universities (PSU, Pitt, Temple) consider applicants on an H4 visa international (aka, 60k cost of attendance) but do check what the situation is for someone who graduates from a PA HS.
Same thing with PHEAA grants for non citizens children who graduate from a PA HS. Look into benefits offered by your employers, either in terms of tuition benefits or scholarships.
The first colleges your child needs to identify is one that they’re sure to get into (acceptance rate for internationals is divided in 2 compared to the typical rate so anything below 25% acceptance rate is an automatic reach no matter their credentials, and you should find colleges where their odds are much higher)- a college they’re sure they will get into, that they like, and that you can afford.
These 2-3 colleges are extremely difficult to identify.
Your child needs to identify what they like about the targets and reaches: small classes? Access to research? Big spectator sports? A thorough core curriculum or on the contrary an open curriculum? Close knit community with residential experience? Strength of alumni network? Etc. Once they’ve identified what they like, we can help identify universities that share these characteristics but would be sure things for your child.
Wrt personal loans, banks won’t lend money for a child’s education when the parents may leave at any point.
An option could be to ask your older child to wait till you have GC but the system is so blocked right now it wouldn’t be fair to have them wait with no deadline in sight, especially since they could try and get a merit scholarship or if you qualify apply to private universities that meet need for the internationals they admit.