nostr:npub1agvvhgh4rftqgz6230ks6xunsrgpg96prfmuvwuuum8s6jz9ehpq589kcr You need a Pixelfed account yes, but you can keep your Mastodon account too

With two profiles you can like/share/comment on posts from each others platforms, think of it like Twitter and Instagram, they both have different meanings to each person