cover cut edge of kitchen worktop
Formica is the material that is usually glued to the countertop.
Normally you clean the top with acetone and put  a “Seamfil” compound with a putty knife.
They have different brands other than Seamfil but pick the brand that most closely matches your color.
There will be a stripe as it never matches exactly but it will seal and keep the material from “puckering” or filling up with Gunk.