Sorryit'ssuchamess!

@Iza L The windows in your bedroom have very nice casing around them - a nice feature and too bad to cover up. Don’t know if you need light control or privacy for the windows but think about either Roman shades mounted at ceiling - above the window trim. Or, maybe wood matchstick rollup blinds also hung above window trim. Both treatments would soften the windows , can provide both light control & privacy, can be used in addition to the blinds currently on the windows. Both treatments will work with the long dresser under the window & both will leave wall space for art & not take visual space into the room as drapery panels would. @ker9 has a good suggestion - I think it was already suggested or something similar. As for guests - we downsized from 4 bedrooms plus den to 2 bedrooms plus den. We now have air beds for when we have more than 2 guests who could sleep in same bed. Air beds have come a long way! We have a full size & 2 extra long twin size. I will admit to also having a upstairs bonus room but we have set the full size up in downstairs den too. All that's needed is to be able to clear floor space. They aren't expensive & it beats having empty bedrooms! And they don't take too much storage space - in a closet or maybe under a bed. ETA - meant to say that trying to fit furniture one already has into a new home isn’t at all unusual!

I would look at Ikea storage systems. Great price and the furniture is good. I recommend either white or grey to work with the current furniture (if keeping) or if you are keeping the bed. The Hauga or the Hemnes would work well with the more traditional furniture you have. However, I would also look at what functionality you want, as any of them would work. With the Besta system, you have a lot more color choices, but there is an upcharge for those colors. They have a really nice light colored Walnut that would look great with the cherry. The Billy system has a lot of bookcases, but not a lot of other choices. Since he doesn't care much and he is 16 (I get it, I had 2 teenage boys), I would get what is best economically for you and could be repurposed for future use in this room or another room in the home. While there seem to be a lot of choices, you can quickly narrow it down, based upon price, color and the items you want. https://www.ikea.com/us/en/cat/storage-organization-st001/?cid=a1:ps%257Ca2:se%257Ca3:US_ActivateConsumerLed_Behavioural_0AO_0en_Search_Brand_HFBMUL_0EM_IKE-IKE-067_IKEA_FY23_Google_CPSA_AOH_Text_Br_Exact%257Ca4:ikea%20closet%20storage%257Ca5:e%257Ca6:google%257Ca7:cq%257Cid:IKEA%2520Branded%2520GM%257Ccc:915

Estate sales, thrift stores and Etsy are good places for original art. Maybe FB Marketplace. If you're decorating your whole home, you may get addicted to estate sales! I have found some really amazing pieces, plus it's been fun to see parts of town that I never would have visited.