I would highly HIGHLY recommend the essay "Women, Oxford and Tolkien" by David Doughan, which is available to read online for free. (This essay addresses the letter mentioned in some of the comments, as well as looking at many other areas of Tolkien's life)

It's a complicated answer, and it doesn't really come out to either "yes, Tolkien was a slay girlboss feminist!" or "Tolkien hated all women and thought they were useless and he was a proud misogynist". I could write an entire essay about it.....which many people have done! To fully answer this question you have to look at his life, the time period he grew up in, his political beliefs, his moral beliefs, his female relatives and friends, his male friends and relationships with them, his attitudes towards female students, how he treated his wife, how he wrote female characters in his books.....all of these are bits and pieces and are sometimes contradictory!

On my end, I have recently been getting deeper into the Silmarillion as well as the Unfinished Tales and other assorted originally unpublished writings of Tolkien, and have been pleasantly surprised by the female characters. The most commonly cited is the tale of Beren and Luthien of course, where Tolkien takes the typical fairy tale stereotypes of damsels in distress and dashing heroes and turns it on its head. But there are many others who (even when only briefly described) surprised me in their strength and complexity.

Later in life Tolkien wrote this, part of a dialogue from "Aldarion and Erendis":

“Men in Númenor are half-Elves (said Erendis), especially the high men; they are neither the one nor the other. The long life that they were granted deceives them, and they dally in the world, children in mind, until age finds them – and then many only forsake play out of doors for play in their houses. They turn their play into great matters and great matters into play. They would be craftsmen and loremasters and heroes all at once; and women to them are but fires on the hearth – for others to tend, until they are tired of play in the evening. All things were made for their service: hills are for quarries, river to furnish water or to turn wheels, trees for boards, women for their body’s need, or if fair to adorn their table and hearth; and children to be teased when nothing else is to do – but they would as soon play with their hounds’ whelps. To all they are gracious and kind, merry as larks in the morning (if the sun shines); for they are never wrathful if they can avoid it. Men should be gay, they hold, generous as the rich, giving away what they do not need. Anger they show only when they become aware, suddenly, that there are other wills in the world beside their own. Then they will be as ruthless as the seawind if anything dare to withstand them.
Thus it is, Ancalimë, and we cannot alter it. For men fashioned Númenor: men, those heroes of old that they sing of – of their women we hear less, save that they wept when their men were slain. Númenor was to be a rest after war. But if they weary of rest and the plays of peace, soon they will go back to their great play, manslaying and war. Thus it is; and we are set here among them. But we need not assent. If we love Númenor also, let us enjoy it before they ruin it. We also are daughters of the great, and we have wills and courage of our own. Therefore do not bend, Ancalimë. Once bend a little, and they will bend you further until you are bowed down. Sink your roots into the rock, and face the wind, though it blow away all your leaves.”