All parties in the Popular Front are generally pro-Palestinians (in particular, Macron's long-standing refusal to even acknowledge that Israel is doing any wrong has been particularly shocking to them, and a good chunk of the population).

In their program they say (translation by me from Le Monde's article):

• they want to "act in favor of the liberation of the hostages detained since the Hamas' terrorist massacres, of whom they reject the theocratic project."
• they also say they want to "immediately recognize the Palestinian State alongside the State of Israël"
• they want to "cut (stop) the French government's culpable support for [Benyamin] Netanyahu's far right supremacist government to impose an immediate ceasefire in Gaza, and enforce the ICJ's [International Court of Justice's] order, which unambiguously refers to a risk of genocide."

As for taxes, there's a lot of stuff (and I'm not translating everything on mobile lol). A lot of it boils down to revertibg all the terribly unbalanced and unfair tax policies of Macron like:

• reestablish the ISF: the tax on one's fortune (generally seen as a rich tax) with a climate twist (not entirely sure what they mean by that, prob gonna make it even hugher if you things like private jets all the time)
• abolish the flat tax: this one's a little complex and I'm really not an expert on this but it's seen as very unqaid. A left MP in 2018 said when this taw was introduced: "Whereas an employee earning 1.2 smic [the minimal salary in France] per month who gets a raise will pay a 14% tax rate on it, a billionaire who earns ten million euros more through a financial transaction will only pay 12.8% tax on this new gain"
• reestablish the exit tax: that was a tax of "unrealized capital gains when taxpayers transfer their tax domicile outside France" (from what I understand, this was meant to fight against fiscal evasion like for when French company heads went to sell their assets in Belgium in which stock sale wasn't taxed. It was supposed to bring about ~800 mil eurosin 2016 had the tax not been removed by then when Macron was Minister of Budget)

• new brackets to make taxes more progressive and fair

• increase their number to fourteen for revenue tax
• establish it in the CSG (generalized social contribution)
• add some more on heritage tax, as well as adding a maximum upon it

They also said they want to add a tax on products depending on how much they travelled throughtout the world (to be produced, I imagine), condition company subsidies to their respect of environemental & social norms (esp fighting discrimination within companies). They also want to tax financial transaction (I'm supposing they mean this at a EU level with the big 'Tax the rich' petition), agro companies super profits.

On a related note, there are lots of stuff they want to do for the lower strada's budgets like:

• make the first few kWh of electricity free of charge each months.
• blocking the prices of some first necessity goods (food, energy, fuel specifically)
• establish minimum prices at which the agro industry will have to adhere to to buy stuff from farmers
• increase budgets for the creation of public lodgings to 1.4B euros (and increase by 10% the youth grants to help them find a place to live)
• revert Macron's reform of the RSA (most basic and lowest income provided by the state that allows people to feed themselves if they don't have a job nor any other gov income like the one for unemployement (post-firing/post-resign to help until the person finds a new job). Macron's reform required that if somebody wants the RSA, they have to work at least 15 hours a week FOR FREE. You can guess how much the people who only had this, including the parts of the population who lives with a handicap took it)
• returning to a max of 32 hours per weeks for physically demanding or night jobs.

(Holy shit this took me one hour to write, hopefully I didn't forget anything)

The Popular Front didn't 'name' him (unless you mean the article). In fact, parties won't 'get' to name anyone, that's the prsident who will pick the PM. However, he has to pick a PM whom a majority of the National Assembly (being elected here) will support, lest it gets 'censored' (destitued) by the Parliement.

JLM is the leader of LFI (even if, particularly in the creation of the Popular Front, his detractors are slowly getting the better of him), and he was LFI's candidate for the 2022 Presidential Election. What the article mentions is that a few days ago, he mentioned on TV that he feels 'capable' of endorsing the role of PM. That does NOT mean the rest of the alliance will suport him (in fact, there's a 0% chance the socialists will).

The people who are more likely to be named as PM (if the Popular Front wins a majority of the Assembly), are either François Ruffin (also LFI, but highly popular, is the one who launched the movement for this Popular Front, and a detractor of Melanchon's), or somebody more moderate without much political clout used to serve as the one on the ejectable seat when Macron's term is over (and said PM is likely to have become unpopular by then).

For their program, I unfortunately wasn't able to find a translation nor a summary in english (tbf, it was published just this friday).

Le Monde has a summary (in french) which you can translate with your favorite translator app if you want.