At 5 months, repetition is good.
Chill. Sounds like you'll burn out before baby reaches 2!
If you go on to have a second child, you may feel horrible guilt when you can't fill every moment with one on one educational stuff for either child.
With DC2&3 I learned that babies love watching day to day life.
Emptying the dishwasher, loading the washing machine etc might seem deathly dull to you but babies love it.
Plonk them on a pile of laundry, pull something gently out from under them, let them feel the clothes, smell daddy's socks. They love it. Chatter away "poo! Smelly socks!".
Prop them up on cushions or a bouncy chair to watch you do stuff. Give them something related to the activity, e.g. a warm teaspoon from the dishwasher.
Sing a long with the radio, have a little dance as you stir the pasta. They love it. Mine sang the radio 2 jingles as well as nursery rhymes.