what should i study to learn everything about cashu, ecash, bitchat, and hash rate ?

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nostr:nprofile1qqsg86qcm7lve6jkkr64z4mt8lfe57jsu8vpty6r2qpk37sgtnxevjcpr4mhxue69uhkummnw3ez6ur4vgh8wetvd3hhyer9wghxuet5qyg8wumn8ghj7mn0wd68ytnvv9hxgvxsf4t

nostr:npub1qny3tkh0acurzla8x3zy4nhrjz5zd8l9sy9jys09umwng00manysew95gx

help!