FYI this property is in NJ

I do not see anything in those pictures that appears to need replacement, It looks to have just been ignored with no maintenance for quite a while.

Thank you for the advice. What would be the right way to fix the windows though? Some of the grates on the windows (outside part) are falling apart

Here’s a better picture of the grates

Your windows appear to be removable. Likewise the panel that they are imbedded in. I’d remove a panel and gently remove the window. Scrape off all the paint that you can. The windows can be repaired. If not by you, by a pro. The windows and the panels are lovely! They just need some TLC. DON’T replace them! They add charm to your home!

Thank you for your replies! Really appreciate your advice! So true, I love the charm, especially on the inside!

Nice room! The windows need the glazing redone and the outside needs fresh paint.

ETA: you can find other on-line resources, but here's one about window glazing. How to reglaze a window

If the wood isn't rotten than scrape and paint will do. Please don't replace the windows the muntins are so fine and charming.

Thank you, everyone!

FYI: muntins and mullions are not the same thing.

Muntins separate the panes of glass. It looks as if your windows are "true divided".. Old doors/windows are very charming, but would never keep out the cold.

Mullions are the cross pieces which divide the windows, as In double hung windows.

You have received good advice, V D, and I am wondering why your landlord isn’t doing the repair?