The healthcare insurance plan that you choose is completely up to you. Kota will only charge your employer for the plan you select, up to the maximum contribution they have set up initially.
For example, if you have selected a healthcare plan whose premium is €70.41/month, and your employer has set up a maximum monthly contribution of €100, you won't be deducted anything for your health insurance, and your employer will only be charged €70.41 every month.
This is not applicable to Kota's health insurance plans for the UK, as these are not selected by the employee. For a UK health plan, the employer will always be charged for the default plan they have selected for their employees - no more, no less than that.