There are good times and bad times to buy your first home; but the bad times have to be pretty bad to be actually worse than not buying. General rule is to buy as early in life as you are able, but don't over-extend. Here are my thoughts to add to everyone else's:
1/ We are very likely to see a fall in house prices. That fall could last a while.
2/ That doesn't mean you shouldn't buy but beware it could mean greater negative equity. If the house price falls below what you paid for it and there isn't much movement in the market you can be trapped if your circumstances change. Unable to move elsewhere and difficulty meeting payments.
3/ It also means that if you waited a little you might be able to get the same house/flat for cheaper. Or a nicer place for the same.
4/ It means that you may be living there for a number of years. You'll be reluctant to sell if you're going to get less than you paid for it. It may take several years for prices to pick up again if they do fall.
All that said, I'd still be inclined to buy. Whilst prices will likely fall you're losing money every month with rent and that offsets it. Buying a house can be quite time consuming so don't think in terms of one months rent but four or five. Sooner started, sooner done.
You sound like you have your priorities right which is that you just want a home. If so then you'll be cushioned from the emotional gutpunch of seeing the home you paid £200,000 for now worth £170,000 because you know it'll go back up again. The value of your home falling doesn't make any material difference to you so long as you're just viewing it as a home. What it does impact is your risk if you were to lose your home / job / whatever.
As regards buying now or in a slump, it depends on how much of a mortgage you need as well. If you hypothetically had the money to buy outright then it would actually be worth it to wait because any fall in house values would be pure savings. But assuming you're an ordinary mortal like the rest of us, mortgages are going to offset that. Interest rates, mortgage offers - they all are adjusted to account for the current market and outlook. At the moment mortgage rates are artificially low because the governments (UK and USA, at least) are working hard to offset the economic impact of Covid-19. They can't sustain that forever.
Without knowing your circumstances and answering generally, my advice is you should buy if you can. Generally it works out so long as you're not an idiot and not greedy. If I could have bought a house earlier in life I'd be laughing right now. If buying a house cleans you out (and it will because there are so many costs you wont think of), try hard to save up enough savings for a few months without income if something happened. That safety blanket will be a big comfort even if you don't need it. You can stick it in something easy to get it back from if you need to like Premium Bonds or whatever is available in your country.
The biggest advantage you can have in buying a home, if you're lucky enough to have it, is a partner who understands long-term thinking and is willing to live a little below your means for the sake of your future together, than someone who insists on getting the maximum house you can afford and buying all the new furniture at once. I spent over two years furnishing my house after buying it. I don't regret it - it was nice to see myself slowly getting what really wanted and be able to afford it. A house is definitely a long-term plan. But usually well-worth it.
I'm also going to leave this here:
EDIT: I just wanted to add that a nice way to look at your mortgage repayments are that the interest payments are analoguous to your rent. The capital repayment part is like saving. So if your rent is £600 and your mortgage repayment is £1,000 then you're paying more out each month. But the if that repayment is £700 paying off the debt and £300 is interest, then what you're really seeing is that your "rent" -i.e. the money that goes 'down the drain' is now £300 less than it used to be. The £700 is like investing / buying equity.
