I purchased a recreational vehicle in 2020 and would like to claim the interest. However, my loan company does not issue a 1098. Can I still claim the interest?

Yes, you can include the interest, even without a 1098, for anything that meets the qualifications for a second home.

where in turbotax do i enter this claim

You would enter the interest for your second home in the mortgage interest section as if you received a Form 1098.  

See the following TurboTax help article to learn more:

Is mortgage interest on an RV or mobile home tax deductible?
 

@macfam