how do i know if a coin is a “scam” or not

i use paper trading on trading view to get practice and i see coins like LAYR3USD and BRAINLETUSD and UNIOUSD, i see them on paper trading but can never find brokers for them and if i do it always seems a little sketchy. does anyone know what brokers let you trade these coins.

and any broker in general i should start with because i dont know what’s reliable.