Can I install new Windows myself?

uh, probably -- as homes that old don't always have 'standard' size windows ... you could run into rotten wood, stringers that are not properly supported, I can imagine all sorts of problems --- I'd hate to see you get in over your head and create problems before they started!

Kudos to you at your age for considering tackling a project like this. I would say it depends upon how strong and agile you are, and the size of the windows. Can you lift and hold them easily? If you were my family member, I would not let you do this by yourself, but I'd be glad to let you supervise.

I have a 60 yr old house... nothing is "standard size" even though several are identical... Had many replaced decades ago, and a few needed significant framing repairs. I'd doubt a 90+ yer old house would be a DIY job!

Yes there may be issues but its not impossible. Look for youtube videos and specifically This old House videos which show the details of the task. The worse possibility is boarding up a window while you figure out the next steps. Enjoy the adventure. https://www.thisoldhouse.com/how-to/how-to-install-replacement-windows

The secret to replacement windows is: be sure you measure them correctly, that is half the battle. Do I at a time, make sure you stuff insulation in the opening where the weights were. And wrap the new window with supplied insulation. It help if you have someone inside and outside, be sure to take the sashes out, do not attempt to replace with sash in. Good Luck!

I love older homes - am in one myself, but it's been a work in progress for many years -- we 'think' a job is going to be 'simple' and some are... but boy oh boy, the ones that have not been!

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