It looks like you're making a typical beginner mistake of confusing mana and lands. This is extremely common, and is one of the problems I deal with several times a year teaching new players, so don't feel bad. I found thinking about the story being told really helps most beginners understand:
- Mana is a temporary form of power/energy/magic, however you want to think about it.
- You can use mana to pay for magic spells, like summoning creatures or throwing a fireball at your opponent, but if you don't use it, it just goes away.
- Mana typically comes from the land you connect with as a sorcerer.
- Each turn, you can connect with a piece of land enough that you can then draw power from that land. The more lands you connect with, the more powerful magic you can perform.
- Once you've drawn on the power of a specific land and gained a mana from it, we tap it to show that it has been used for the turn, but you'll still be able to use it again next turn.
- There are five types of lands that are most common and produce just the five basic forms of mana, White, Blue, Black, Red, and Green.
- Some land, however, can provide you with more than one color of mana. Mistvault Bridge connects a place with abundant water to a place of death and decay, so you can draw upon it once each turn to get blue mana or to get black mana.
Another thing that would be helpful would be to look at what a basic land actually does. When I started learning Magic, an
Island actually said "Tap: Add one blue mana to your mana pool." (It had the symbol for "tap" and "one blue mana", not the words, but you get the idea.) That's what all basic lands actually mean, even now, but the game designers have tried to
simplify it, which, unfortunately, can lead to confusion for beginners.