Can I just read the lyrics from my phone while recording?
You can, and it is the single most common reason a vocal take sounds dull. The phone pulls the head down and off axis, the screen sleeps, and notifications arrive mid-song. A DAW-synced prompter at eye level fixes the sound as much as the lyrics.
A large-diaphragm condenser is directional and sensitive to angle. Singing five degrees down into it takes the top end off the voice, and no amount of EQ later puts it back convincingly.
That is why phone-read vocals often need more brightening in the mix than the same singer sounds like in the room. The lyrics were not the problem; the posture they caused was.
No card required. Install the VST3, paste a lyric sheet, and record one take end to end before you decide.
An old monitor, a TV with an HDMI input or a tablet running as an extended display all work. The prompter does not care which.
That is where it helps most, because there is nobody else to scroll for you.