Friend or foe?

Hey guys, as always i find myself turning to the forums in search of an answer!

As stated in previous posts of mine i am a new gardener this year, and am in the process of putting out my seeds that are ready to be put out at this time of the year, however i realised after i had put them out that A: i did a good thing weeding the hell out of the flower beds before sowing and B: that i have also screwed myself over slightly, as i am not 100% sure what i am going to do when my seeds start coming up.

I have planted my seeds in small channels so when they are small they should come up in rows, but heres the thing, how will i know if that stray thing growing is a seed or a weed? ofc some of the weeds have distinctive shoots and im fine with that but i am not very confident that i'll know when to pluck something out or when to leave it be ?

Please help with your ideas or solutions, as im sure many of you have great answers to this !

Mark.