Noob Question about ETH

I have never really followed ETH. I do have some but honestly I was thinking of selling it all to get some cryptos that seem very low / underpriced (on sale) right now.

Am I big stupid for wanting to sell? Can someone advise me please? Would you sell any ETH right now, to try to get some gains in another crypto you believe in? Honestly not sure if saying which is even against the rules or taboo here, its my first post after all.

Thanks ETH boys. Sorry for not being more in the loop.