@Jain I am aware of Tusky - using it right now.
Can I use my Mastodon account to browse a Lemmy community, see the list of posts, open a post, vote up/down the comments?
AFAIK, I can't. There is no unified client that can let me do that from the same account. If I want to access something through the Lemmy interface, I need a Lemmy client, which can only interact with Lemmy servers. Same with "Mastodon-compatible" servers and clients.