You can apply for the registration of your trademark directly online by downloading and filling out the pdf form.
A trademark registration is valid for a period of 10 years. Your trademark will be protected for the duration of this period. You can renew your registration at the end of the 10-year period.
To maintain the right to your trademark you need to use it actively.
See the link for the associated fees. If your trademark cannot be registered after all, the filing fees will not be refunded.