I installed windows 7 on a laptop that came with windows 10 and now I cant find drivers for it.

If support site doesn't have windows 7 drivers, then you have to manually search for compatible drivers.
And it's not guarantied, that you'll find them for all devices.

Just download windows 10 installation from microsoft and reinstall windows 10. Windows 10 install key should be integrated into your laptop BIOS. If you install the right windows 10 version, you won't be asked for key.
https://www.microsoft.com/en-us/software-download/windows10

no such thing as universal drivers. they have to be coded for each OS. true you often download a single package that covers all versions but if you look at it unpacked you'll see separate folders for each OS.

you'll have to be VERY comfortable searching and trying out various drivers to see if you can any one to work. i've done this many times and it is never easy nor a quick process. nor is it always 100% successful. you can edit the ini file for a win 10 driver and MAYBE get it to install and work on win 7. but there is no guarantee it will work. windows vista and win 8 drivers were easier to get working on win 7 since they are closer in relation than win 10 is.

you can google how to get win 10 driver ini files edited to work on other win versions as a first shot. it's not that hard to do but can be hard to find the right line to edit at times.

what i usually end up doing and what has the most success for me is to look at the individual parts installed. see what the LAN/WIFI card installed is and go to that manufacturer site and see if they have older drivers for the part. get the LAN or wifi working and windows update might be nice and get some other drivers for you. if not, keep looking up parts 1 by 1 until you have working all you can. possible you can find win 8/vista drivers that can then be modified to install to your win 7 using the editing skill you learned from the above step

overall, this will be time consuming and not easy to do. gotta ask yourself if it is worth the time to have win 7 and not win 10. i do this a couple times a week for clients and i charge a lot to do it since it is so much work!!