How do I replace the trimmer line on the whipper snipper?

Rebuild or replace the carburetor. Whichever is cheaper and that should solve the problem

If you need further help, I’m available over the phone at https://www.6ya.com/expert/kelly_69a0cf1b13789df1

cutting hubs on trimmers are held on by a left hand thread nut
turn the hub center / nut in the right direction ( as if doing it up)and it will come undone

What is your question about this?

I think that might be a K-Mart line of products

This Homelite gas trimmer runs on a 50:1 mix of unleaded automobile gasoline and two-cycle engine oil. That is equivalent to 2.6 fluid ounces (80 ml.) of oil to one gallon of gasoline or 4 tsp. (20 ml.) of oil per quart of gas, or 2 tsp. (10 ml.) of oil per pint of gas. Don't use automotive motor oil or two-cycle outboard motor oil in your Homelite gas trimmer; they contain additives detrimental to trimmer performance. Use mixed fuel within 30 days.

I never heard it called a whipper snipper before but I am on this side of the ocean. you should be able to go to www.ryobiuk.com. Put in your model number and you should find a parts list for it.
HTH
Good Day. mate

This was answered in a previous solution

Hold the snipper upside down so the petrol leaks onto the kitchen floor. Take 6 metres of line and untangle it eventually. Stick it through the two holes and wind the cord in opposite directions so it jams together and tangles. Stick the unit head back together with two feet of line sticking out each side. Start the trimmer and jump backwards as the line rips itself to pieces. Use it on weeds until line breaks within 20 seconds. Slam the end of the trimmer into the concrete and shout **** fuckey **** ****. Then tear off the head cover and start again. I have done this for years and it never fails. Hope this helps.