Re: i’ve been trying to get my sims pregnant but i don’t know how. can anyone help ?

Make sure one of the sims is able to get others pregnant and the other is able to get pregnant, you can check this in CAS (top left, below the buttons where you choose their gender, there is a drop-down menu that lets you change this) but all male sims can get others pregnant and all female sims can get pregnant by default.

If that's not the issue, you need to make sure your sims have high enough romance with each other, about 40% of the romance bar should be full. You'll have the option to "Try for Baby", so do that. If it doesn't work the first time, keep trying. 

Hope this helps!