Can new shocks take a while to break in

There are a few things in this. One you were used to the old worn out parts, they were likely not providing much damping so they would feel soft. The new parts have full damping, new bushings and unless they were the same parts as the OEM units they may be a bit stiffer.
Did you replace all 4 corners? If so it isn't so much that they have to break in as much as you need to get used to the new parts. It would be like you getting a brand new Rav4 from 2002, yours has worn in and the new one will feel entirely different. This happens a lot when you take a vehicle that has miles on it and replace the suspension parts, suddenly it rides and handles like it did 17 years ago.

Thanks so much for your prompt response.
Oh, I only replaced the front shocks with the two new tires. How long do you think it will take to get used to them.

Shouldn't take that long. I would suggest replacing the rears as well if they have the same amount of miles/wear. It will improve the ride and handling because the damping will be the same in all 4 corners. Plus if they are all new they can wear together.