hello do you know how can I modify the level of the skills to level 10 and how can I disable them?

Ctrl + Click while in the upgrade menu on an upgrade to decrease the level of the skill.
Going into "Mod Options -> Goki Stats -> Config -> global modifiers" will show a list of multipliers so you can change the rate of which upgrades give stats.
Otherwise, you may use /xp (experience amount) with cheats on to grant yourself enough experience to purchase up to level 10 for the skill(s). If you're playing survival, just mine, smelt or kill mobs to get some xp.