The first thing I might do is put it up on a plant stand so that it can get more light from the windows. At the current location it is going to keep reaching for the light, which will make it more lanky. What direction do those windows face?

Are you wanting to straighten the trunk or the branches? If the latter, one thing you can do is prune some of the tallest growth and prune in some of the wider growth at the side. This should encourage branching during the next growth cycle. Then you repeat. It can take years to get it more round, and it will have an impact on fruiting in the next year. Another option, and you want to be careful with this one because if you change too much too soon you can break branches, is to wire branches that you want to keep to put them where you want. Look up bonsai wire techniques. It takes awhile for the tree's branches to set in the new location. So it takes patience. Alternatively you can bend the branches and tie them off with jute twine to relocate them. I've used both on my Nagami, but it can take 6 months to a year or longer for the branches to set in place so you can remove whatever you're using to brace the branches.

Plant stand is a great idea, I will definitely do that. Its between and western and north western window do it gets a lot of light, not always direct but definitely the brightest place in the house. Should I be fertilizing? Also how much do you recommend watering? I usually just give it some water sometimes, not a great “schedule” 😂 and never drench it because the pot is so big compared to the plant. The leaves started yellowing last week and I had watered more than usual.

Very simple...if you want to straighten the plant use a shop vac and remove potting soil from the side you want to move towards. Once you have removed a couple of inches of soil along the pot wall it is easier to shift the root ball. The weight of the MEYER Lemons is too much and that is why it is leaning. You need to provide some support or risk them snapping off. In this photograph you can see a green stake in the center, bamboo supporting oranges and wire support to help the tree to continue growing straight. The bamboo came from a dollar store, as did the vinyl coated steel rod. The 2x black powder coated wire frame came from a garden center. The two frames are attached with tie straps.

Try a 12" sunblaster LED with stand pointing upward. (see background in photo). That would augment the light in the window.

looks like a meyer lemon tree. You've done well to keep it going.

Lemon!! Wow. Nice work. Now for the huge question..What the heck is your electric bill? What lights are you using and how close? Good work)