When your stones wear and are.no longer flat, it's hard to get a fine edge. It gets more and more frustrating.
If the knives aren't high quality, then a cheap carborindum from a discount store will serve you well for practice and starting with a square flat surface .

There's umpteen instructionals on YouTube.
Lots of good advice.

Here's one. Cliff is a good farmer who likes all things sharp.
Do a search and you'll find one here on basic how to.
https://m.youtube.com/user/CliffStamp/videos

Do you have a family member who is a barber, meat cutter, machinist?
They will do it for you for buying them lunch.

Blessings,
Happy Camper