Welcome to the forum. Congratulations for making the decision to start your journey again. The people on the forum are a wealth of knowledge & are pretty inspirational (there's lots of mums too) so I'm sure you'll love it here.
Losing weight to conceive is a pretty BIG incentive to lose weight. I'm on the exact same journey! I've been on my journey for just over 3 months & found that the thought of producing the miracle of life is enough inspiration to keep me on track. I don't follow any particular "diet" - just sensible healthy eating accompanied by regular walking. It works for me but different things work for different people...It's a lifestyle change that has benefited my whole family.
Pregnancy is different for everybody so it's hard to give advice on how your weight will affect your particular pregnancy. Being fit & healthy at the time of conceiving has obvious benefits for mother & baby and lessens the risks of complications. I think we should do all that's possible to give ourselves the best chance of a healthy pregnancy & healthy baby (I have learnt from my past experiences).
Jump on board and let the journey to a healthier happier you BEGIN! Will you be starting before or after the easter eggs tomorrow
Good luck with your journey.