1. My mom made pizza. My family liked it.

2. My mom made pizza. I want to make one, too.
3. My mom made pizza. I want to make it, too.
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#1 is correct. What about #2 and #3?
Whic one is correct? Do we have to use 'one' or 'it'?

1 and 3 are correct as they are.

2 will be correct (and make sense) if you add "a" before "pizza" in the first sentence. Then there's one pizza for the second sentence to refer to!