Which hero to claim and what to use silver bricks for?

Hey everyone I am new to the game, lvl 21, our server’s still at Season 0, and I am mostly f2p having spent only for a second builder. I joined only two weeks ago.

I want to know the best way to get stronger since I spend only a little and would need to maximize any resources I have.

Can someone advise me on what to focus on with my first team? Like who should I level up first, which shards should i get from the chests (like do i unlock the ones i dont have yet?), and whose skills do i invest in? Dont get me started on UR equipment, it takes forever to craft them so right now I only have a two attack pieces for Kim, 1 defense piece for Murphy, 1 attack piece for Mason. Any advice regarding equipment would be welcome!

And lastly, i am unsure what to spend the silver bricks for, is it correct that i should save up for glittering market red blueprints instead of buying other things?

Any advise is much appreciated, thank you!