Http error when uploading images

Hi! I’m not very knowledgeable in working with wordpress, and lots of answers I found for this online were too complicated for me to understand, so I thought it’d be good to ask about this as a more specific case. When I try to upload media to a post, the uploading bar get’s stuck about a third of the way, and eventually gives me an HTTP error, without any more information. I’ve been uploading the exact same size and type of images to the site for a couple years (so I know it’s not an issue with the image itself), and haven’t changed anything about the site recently, but suddenly this error has been appearing every time. I’ve tried a couple random solutions I found on the internet, but it seems this is a very general issue, are there any first steps I should take to figure out what’s causing it?

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