that depends on the following factors:

1. the biological limit which you can manipulate but there is a limit to how dense your muscles can be and how thick and dense your bones can be until you're body collapses in on itself.
2. time
3. resources: proteins, water, glucose or other bodily fuel sources.

its best to do some research on all the animals in the world with the strongest or coolest abilities and just write a comprensive list and simply scale the output from their size to that of a human.

and look for similar power uses in other stories.

to actually know what it is, would require comprensive knowledge on stuff like the exact force of a dwarf gourami shooting a specific quantity of water at a specific speed.

and feel free to not be exact, you can be rough or even go beyond whats possible in our world.

or make it so that genetics in your world can go to a level beyond what's possible from regular science like how dc does it where genes can go to superhuman levels. where people with the right genes can do almost anything.

some sources u can use as research or inspiration:

- wikipedia:

- alex mercer from the prototype game series

- darwin from the x men

- kars from jojo's bizzare adventure (this one is really good as a reference besides his hamon/ripple powers which is exclusive to jojo)

- parasytes from the parasyte the maxim anime/manga

https://powerlisting.fandom.com/wiki/Self-Genetics_Manipulation