Weight gain during pregnancy

This may be a ridiculous question but I’m really concerned so I’m asking.

I am 35, 5’2 and 205lbs. I am trying to conceive.

I have been trying to loose weight, but I’m hoping I’ll be pregnant soon.

My concern is that I can not loose the amount of weight I want before I get pregnant. I don’t want to wait because of my age.

I am terrified of gaining more weight while pregnant because of all the health risks. Will I automatically pack on even more pounds when I get pregnant, or can I keep myself from gaining much more by keeping up with my healthy eating and exercising?

I don’t know if anyone has gone through anything similar?

Thanks for any help