The nation's employment picture continued to brighten in April as half a million persons found jobs and the unemployment rate fell to a 29-month low of 7 per cent, from 7.3 per cent in March, the Labor Department reported yesterday.

The unemployment rate as already declined to the level the Carter administration hoped it would reach the end of this year. Since the November election the rate has fallen a full percentage point.

While nearly all labor groups benefitted from the increase in jobs - 90 million persons are now at work - experienced workers, mainly adult men, continue to fare better than inexperienced workers, mainly teenagers and women.

In March and April alone the American economy created a million jobs, a performance Commission of Labor Statistics Julius Shiskin called "fantastic." But AFL-CIO President George Meany said a 7 per cent jobless rate is "nothing to brag about."

The April employment report demonstrates that the economy has sucessfully shaken off any lingering effects of the disclocations caused by the severe cold weather and natural gas shortages of January and early February.

It should also strengthen President Carter's case that the $50-a-person tax rebate, fashioned in January to stimulate an economy thought to be faltering, is no longer needed. Many Democrats were angered by Carter's sudden abandonment of the proposal last month.

On the other hand, the glowing employment reports of recent months have been accompanied by sobering reports on inflation. Wholesale prices have been rising at 13.1 per cent annual rate during the last three months and consumer prices have been climbing at a 10 per cent rate.

While the employment picture has been improving, at 7 per cent the unemploymnet rate remains very high by historical standards, especially since an economic recovery has been under way for nearly two years.

Since the low points of the recession in May 1975, 5.5 million persons have found jobs and the unemployment rate as fallen from 9 per cent to 7 per cent.

Still, 6.7 million persons were jobless in April.

The unemployment rate us defined as the percentage of the labor force which is not working but is actively seeking work. The labor force is the total of those looking for work and those at work.

The Labor Department bases its reports on a monthly survey of 47,000 households. It adjusts the rate to account for normal seasonal ups and downs in employment.

Commissioner Shiskin told the congressional Joint Economic Committee yesterday of a continuing "two-tier pattern" in the economy, "with younger workers taking one path - that of continuing high unemployment - and experienced workers taking another path - that of fairly strong decline" in unemployment.

The decline of two percentage points since May 1975 in the overall unemployment rate is a 22 per cent drop. The rate for experienced workers who had been laid off fell 40 per cent, while "there has been little change for everybody else - new entrants, re-entrants and job-leavers - who are mostly teenagers and women," Shiskin said.

Rep. Henry S. Reuss (D-wis.), chairman of the House Banking Committee, said the existence of this two-tier unemployment picture justifies removing the general economic stimulus that a tax rebate would have provided.

Reuss said the government must develop targeted jobs programs that seek not to boost employment by increasing overall demand but pinpoint groups which find it hard to get jobs - such as women, minorities and youth.

All major groups of workers had lower unemployment rates in April. The rate for adult men fell from 5.4 per cent to 5 per cent. The rate for adult women declined from 7.2 per cent to 7 per cent, while the teenage unemployment rate feel to 17.8 per cent from 18.8 per cent. For blacks the rate declined to 12.3 per cent from 12.7.

Construction workers, whose unemployment rate had been as high as 21 per cent, fell to 12 per cent in April from 14 per cent in April from 14 per cent in March. There were also fewer persons working partime who wanted to work full-time.