Adding new effects for skills.

Hello. I was recently reviewing the skill tree and wanted to slightly enhance the central perks for each faction. I only have a basic understanding of scripting, but I would like to add something new to the game. For example:
For the "Unrelenting Force" skill, using scripts, add, in addition to increasing vigilance, a double attack for both melee and ranged units.
For the "Scream of Terror" skill, in addition to reducing morale, also add the "Grief" spell, which would be constantly applied to all enemy creatures, and so on.
I want to create a small mod for H5.5. I would be very grateful if someone could help me with this.