Laptop: Dell Inspiron 7520

Processor: Intel Core i5-3210M CPU @ 2.50GHz

Installed RAM: 6 GB

Charger: 90 watt HP charger

So I had to get a new charger for my old hand-me-down laptop after I accidentally tripped over the cord and broke the tip. I went down to my neighbourhood tech store after calling ahead and telling them my situation. They told me on the phone that they have chargers that will cover any and all Dell laptops. When I got there the guy gave me an HP charger but told me as long as they are the same wattage and voltage that it will work. When he booted he said something about looking for a screen to find out about the charger but I didn’t hear him clearly and I also couldn’t see the display. After booting it and logging in, he checked the battery icon on the taskbar and it said, “Not charging.” I was confused but I had also told him that my battery was already barely functioning and that I didn’t know if it had the ability to pull a charge before. Even with the original Dell charger, it would last less than a minute before going into sleep mode to conserve power if it was unplugged. When I finally got home and booted the computer myself, I was greeted with a black BIOS screen that said something like, “the AC adapter wattage and type cannot be determined. The battery may not charge. The system will adjust the performance to match the power available.”

I’m wondering if this will impact my computer’s usability or even flat out if it’s safe to use. I’m a complete novice so any help or insight would be greatly appreciated. Should I be okay or should I return this thing, get my money back, and try to find an exact replacement online? Thanks again!

So I have had this computer for a while and need it for school, but earlier this year the charger or the computer refused to gain charge.

But it was only recently that I was able to get it to best buy for a very basic inspection. After telling them the problem, they told me that the charger itself was the problem. So im trying to find the right one but non of the chargers seems to be the correct one. They all are the usbc universal.

Like the image 2nd pic shows, that is not the correct one (at least i dont think so) , so can someone please help me or tell me what the correct charger is?

I wrote this on my phone so sorry if the text looks off.

I have an old dell Inspiron laptop with an Intel core i7 8th gen (this is the only spec I am sure of). I haven't used it in years and was thinking of repurposing it into something like a server. However I do not have the charger for it, so where would I be able to buy a new one?