I can't delete my mods

what platform are you using for your mods?

If you have MC open while trying to delete the mods it wont work.

Also, if you are using a seperate instance of minecraft, you can try ingame going into the resouce pack section hitting open resoucepack folder and go back to the previous file, find mods and you can find them there. Apologies for the bad writting it is almost midnight for me.

If you could record what you mean by "can't" or atleast give us your log, somebody could probably find a solution. (PS. programs like OBS are the best option for recording!)

Head over to C:\Users\<username>\AppData\Roaming\.minecraft\mods
OR C:\Users\<username>\AppData\Roaming\.minecraft\instances\<forge_version>\mods
AND delete/remove the files from there.