I received some lilac bulbs with beautiful lilacs blooming and there in a glass vase
I have never seen lilac bulbs and wanted to know if you can plant them outside

Do you have a photo? Lilacs are shrubs and they don't grow from bulbs. The blooms of Hyacinth bulbs can resemble lilacs. Is this what you have?

zuzu is correct - Lilac's are not bulbs, they are shrubs. So we are not really sure what it is you are referring to.