is there a set or series of videos or other medium for learning thinkscipt (for ThinkorSwim Platform)from the begiining to advanced? I want to learn how to code my own indicators and trading strategies.

here're 2 videos from Eric (who's behind thinkscripter.com):

in addition, ToS official tutorial is a good start: https://toslc.thinkorswim.com/center/charting/thinkscript/tutorials.html

lastly, you may find Read the Prospectus blog helpful: https://readtheprospectus.wordpress.com/the-complete-beginners-guide-to-using-custom-thinkscripts/

thank you!