There is an income limit for Roth IRA contributions (or more specifically, there is an income-based phaseout range, over which the annual contribution limit gradually drops from $6000 to $0). You can see the phaseout ranges for 2021 here.
It's worth mentioning that even if you are over the income limit for direct Roth IRA contributions, you may still be able to do a "backdoor Roth IRA contribution". This is where you contribute to Traditional IRA, and then convert it to Roth IRA. Neither Traditional IRA contributions nor Roth IRA conversions have income limits. If you do not have any existing pre-tax money in Traditional/SEP/SIMPLE IRAs (and do not contribute or rollover any pre-tax money into Traditional/SEP/SIMPLE IRAs for the rest of the year), then you will not have to pay any tax in the "backdoor Roth IRA contribution" process, and the result will be essentially identical to a direct Roth IRA contribution.