No, you don't need a new avatar. And you don't need weapons or anything but tools.

Select tool.worlds to filter out everything else.

Then, before you buy anything, decide what you are after. Just TLM? Then the number in the top left corner matters. Higher is better. Points to exchange for AlienWorld NFTs? Then the number in the lower right corner matters, and the NFT must be of common rarity or better.

After that, you'll need to pick a good land to mine on.

The Charge Multiplier and the delay of your tool(s) decides how long each mining attempt takes, the land's Mining Power and your toll(s) difficulty decides the TLM you get, and the land's NFT power combined with your luck decides NFT points. All according to some formulas I have forgotten, but you can probably find them by googling. Commission is just that, how much of your loot the land owner takes.

Some lands have raffles for non-AlienWorld NFTs, giving you a ticket for each mining attempt. CryptoMonkeys and myzicklearmy are the only ones I can remember right now, but there are more.

Good luck with the mining!