Can I share an Apple ID with my husband

Presumably your phones will have different numbers from your telephone company. You shouldn't be getting calls on a phone with a different number. An Apple ID has nothing to do with that. However, you are right to be concerned because if you were using FaceTime or any other Apple service where an individual is defined by an Apple ID then you would both be seen as one person.

I think the document at this link should answer some of your questions about Apple IDs:

Click on this link for Apple ID Frequently Asked Questions --> https://appleid.apple.com/faq

How to create a new Apple ID - Apple Support

Depending upon how long you have been using a single Apple ID there may be some work involved in transferring data from one ID to a second one. You may also need to set up Family Sharing to share purchases and items you do wish to both have access to.

Apr. 2018 post by ASC helper Winston Churchill on transferring data from one Apple ID to another. https://discussions.apple.com/message/33333380#message33333380

Feb. 2021 tips from Eric Root https://discussions.apple.com/thread/252468781?answerId=254653802022#254653802022

Look into using Family Sharing to continue to be able to use items purchased with one Apple ID with other Apple IDs.

What is Family Sharing? - Apple Support

Set up Family Sharing - Apple Support

You say "my phone" which to me implies he has his own phone, hence my though that two phones are involved. If you are sharing a phone, you cannot have two Apple IDs active on an iPhone at the same time. You could block calls being made to him on your phone but only by using methods such as you would employ to stop a telemarketer.

Block phone numbers, contacts, and emails on your iPhone, iPad, or iPod touch --> https://support.apple.com/HT201229

Normally, you can't block his calls. Apple IDs aren't meant to be shared. You might consider getting your own Apple ID.