Are those against euthanasia and those against abortion mostly the same people?

I'd say the vast majority of those in favor of euthanasia also support a woman's right to choose.
Some walk the walk when it comes to freedom.

I certainly think the arguments in principle against both have something in common. But when it comes to legislation, there’s a big difference. Euthanasia can, to a large extent, be prevented by legislation, whereas abortions will happen whatever the law. Replacing dangerous “backstreet” abortions with safe regulated ones was a major factor in the original UK Abortion Act in 1968.

in favor of both. it's your body and you have the right to do whatever you do with it

Actually, most of the people I know who support a woman’s reproductive rights also support death with dignity laws. Bodily autonomy in both cases.