New strategy 50% holding 50% swapping : BTC and ETH to WBTC and WETH

First of all i wanna salute you all !

Second, am i stupid enough or i need a bit more to be 100% ?

ok..

So i need your help now, never done this and i want to try it out, i want to make a lot of swaps and i heard that wrapped coins have less fees, but i don't know where and how to start.

I have two options, Polygon chain or Bsc chain, which one you recommend should i go with? and why?(pros/cons) if possible.

Which one is more expensive? more secure?

Any details, anything you have is welcome!

I would appreciate if you share your experiences with me.

Thank you very much indeed for your time !