Not sure, what you mean. A thyristor can be used in a free running trigger generator (e.g. for a stroboscope). A diac or a zener diode (in case of a sensitive gate thyristor) is firing the thyristor, when the storage capacitor voltage reaches the defined threshold.
i saw different kinds of gate circuits, there are dc, pulse and ac signals. hm most of them are complicated
i mean can i implement and design my own circuit ( create a circuit ) used for generating triggering signals for SCR
You should try to be more clear. How do you want to fire the thyristor, e.g phase angle control, on/off control?
There are several aspects involved in trigger circuit design, e.g. isolation (possibly by trigger transformers), generating high trigger currents (for large thyristors) with limited supply power, possibly zero crossing detection and timing generation for phase angle control, timing for full wave switching.